Download 9278654 PS/Chemistry Ja03 - Dolgeville Central School

The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Wednesday, January 29, 2003 — 9:15 a.m. to 12:15 p.m., only
You are to answer all questions in all parts of this examination according to the
directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
Your answer booklet for Part B–2 and Part C is stapled in the center of this
examination booklet. Open the examination booklet, carefully remove your answer
booklet, and close the examination booklet. Then fill in the heading of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for your use while taking this examination.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
1 Which statement best describes electrons?
(1) They are positive subatomic particles
are found in the nucleus.
(2) They are positive subatomic particles
are found surrounding the nucleus.
(3) They are negative subatomic particles
are found in the nucleus.
(4) They are negative subatomic particles
are found surrounding the nucleus.
6 Which Group of the Periodic Table contains
atoms with a stable outer electron configuration?
(1) 1
(3) 16
(2) 8
(4) 18
and
and
and
7 From which of these atoms in the ground state
can a valence electron be removed using the
least amount of energy?
(1) nitrogen
(3) oxygen
(2) carbon
(4) chlorine
and
2 During a flame test, ions of a specific metal are
heated in the flame of a gas burner. A characteristic color of light is emitted by these ions in
the flame when the electrons
(1) gain energy as they return to lower energy
levels
(2) gain energy as they move to higher energy
levels
(3) emit energy as they return to lower energy
levels
(4) emit energy as they move to higher energy
levels
8 What is the percent by mass of oxygen in
H2SO4? [formula mass = 98]
(1) 16%
(3) 65%
(2) 33%
(4) 98%
9 An atom of carbon-12 and an atom of carbon-14
differ in
(1) atomic number
(2) mass number
(3) nuclear charge
(4) number of electrons
3 In which list are the elements arranged in order
of increasing atomic mass?
(1) Cl, K, Ar
(3) Te, I, Xe
(2) Fe, Co, Ni
(4) Ne, F, Na
10 The strength of an atom’s attraction for the electrons in a chemical bond is the atom’s
(1) electronegativity
(3) heat of reaction
(2) ionization energy
(4) heat of formation
4 In which compound does chlorine have the
highest oxidation number?
(1) NaClO
(3) NaClO3
(2) NaClO2
(4) NaClO4
11 Which type or types of change, if any, can reach
equilibrium?
(1) a chemical change, only
(2) a physical change, only
(3) both a chemical and a physical change
(4) neither a chemical nor a physical change
5 Which event must always occur for a chemical
reaction to take place?
(1) formation of a precipitate
(2) formation of a gas
(3) effective collisions between reacting particles
(4) addition of a catalyst to the reaction system
P.S./Chem.–Jan. ’03
12 An increase in the average kinetic energy of a
sample of copper atoms occurs with an increase in
(1) concentration
(3) pressure
(2) temperature
(4) volume
[2]
16 One similarity between all mixtures and compounds is that both
(1) are heterogeneous
(2) are homogeneous
(3) combine in a definite ratio
(4) consist of two or more substances
13 The empirical formula of a compound is CH2.
Which molecular formula is correctly paired
with a structural formula for this compound?
(1)
(2)
(3)
C2H4
C2H4
C3H8
H
H
H
C
C
H
H
H
C
C
H
H
H
H
H
C
C
C
H
H
H
17 Which phase change results in the release of
energy?
(1) H2O(s) → H2O()
(2) H2O(s) → H2O(g)
(3) H2O() → H2O(g)
(4) H2O(g) → H2O()
H
H
18 Which compound has an isomer?
H
H
(1) H C H
(4)
C3H8
H
H
H
H
C
C
C
H
H
H
H
H
H
H
(2) H C C H
H
H
H
H
(3) H C C C H
H
H
H
H
H
H
H
(4) H C C C C H
H
H
H
H
14 Given the equation:
F
+
1e –
–
19 What occurs when NaCl(s) is added to water?
(1) The boiling point of the solution increases, and
the freezing point of the solution decreases.
(2) The boiling point of the solution increases, and
the freezing point of the solution increases.
(3) The boiling point of the solution decreases, and
the freezing point of the solution decreases.
(4) The boiling point of the solution decreases, and
the freezing point of the solution increases.
F
This equation represents the formation of a
(1) fluoride ion, which is smaller in radius than
a fluorine atom
(2) fluoride ion, which is larger in radius than a
fluorine atom
(3) fluorine atom, which is smaller in radius
than a fluoride ion
(4) fluorine atom, which is larger is radius than
a fluoride ion
20 Which radioisotope is a beta emitter?
(1) 90Sr
(3) 37K
(2) 220Fr
(4) 238U
15 The high electrical conductivity of metals is
primarily due to
(1) high ionization energies
(2) filled energy levels
(3) mobile electrons
(4) high electronegativities
P.S./Chem.–Jan. ’03
21 When a mixture of water, sand, and salt is filtered, what passes through the filter paper?
(1) water, only
(2) water and sand, only
(3) water and salt, only
(4) water, sand, and salt
[3]
[OVER]
27 When a neutral atom undergoes oxidation, the
atom’s oxidation state
(1) decreases as it gains electrons
(2) decreases as it loses electrons
(3) increases as it gains electrons
(4) increases as it loses electrons
22 A hydrate is a compound that includes water
molecules within its crystal structure. During an
experiment to determine the percent by mass of
water in a hydrated crystal, a student found the
mass of the hydrated crystal to be 4.10 grams.
After heating to constant mass, the mass was
3.70 grams. What is the percent by mass of
water in this crystal?
(1) 90.%
(3) 9.8%
(2) 11%
(4) 0.40%
28 Given the equation:
C(s) + H2O(g) → CO(g) + H2(g)
Which species undergoes reduction?
23 Which of these 1 M solutions will have the highest pH?
(1) NaOH
(3) HCl
(2) CH3OH
(4) NaCl
(1) C(s)
(2) H+
29 Which equation is an example of artificial transmutation?
(1) 94Be + 42He → 126C + 10n
(2) U + 3 F2 → UF6
(3) Mg(OH)2 + 2 HCl → 2 H2O + MgCl2
(4) Ca + 2 H2O → Ca(OH)2 + H2
24 Which physical property makes it possible to
separate the components of crude oil by means
of distillation?
(1) melting point
(3) solubility
(2) conductivity
(4) boiling point
30 Which species can conduct an electric current?
(1) NaOH(s)
(3) H2O(s)
(2) CH3OH(aq)
(4) HCl(aq)
25 In saturated hydrocarbons, carbon atoms are
bonded to each other by
(1) single covalent bonds, only
(2) double covalent bonds, only
(3) alternating single and double covalent bonds
(4) alternating double and triple covalent bonds
26 Which formula correctly represents the product
of an addition reaction between ethene and
chlorine?
(1) CH2Cl2
(3) C2H4Cl2
(2) CH3Cl
(4) C2H3Cl
P.S./Chem.–Jan. ’03
(3) C2+
(4) H2(g)
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
31 According to Table N, which radioactive isotope
is best for determining the actual age of Earth?
(3) 60Co
(1) 238U
90
(2) Sr
(4) 14C
36 Hydrogen has three isotopes with mass numbers of 1, 2, and 3 and has an average atomic
mass of 1.00794 amu. This information indicates
that
(1) equal numbers of each isotope are present
(2) more isotopes have an atomic mass of 2 or 3
than of 1
(3) more isotopes have an atomic mass of 1 than
of 2 or 3
(4) isotopes have only an atomic mass of 1
32 Given the following solutions:
Solution A: pH of 10
Solution B: pH of 7
Solution C: pH of 5
Which list has the solutions placed in order of
increasing H+ concentration?
(3) C, A, B
(4) C, B, A
33 Which statement explains why nuclear waste
materials may pose a problem?
(1) They frequently have short half-lives and
remain radioactive for brief periods of time.
(2) They frequently have short half-lives and
remain radioactive for extended periods of
time.
(3) They frequently have long half-lives and
remain radioactive for brief periods of time.
(4) They frequently have long half-lives and
remain radioactive for extended periods of
time.
38 Given the reaction:
S(s) + O2(g) → SO2(g) + energy
35 Which of the following solids has the highest
melting point?
(3) SO2(s)
(1) H2O(s)
(2) Na2O(s)
(4) CO2(s)
P.S./Chem.–Jan. ’03
Reaction Coordinate
Reaction Coordinate
(1)
(3)
Potential Energy
34 A compound whose water solution conducts
electricity and turns phenolphthalein pink is
(1) HCl
(3) NaOH
(2) HC2H3O2
(4) CH3OH
Potential Energy
Potential Energy
Which diagram best represents the potential
energy changes for this reaction?
[5]
Potential Energy
(1) A, B, C
(2) B, A, C
37 Which list of elements contains two metalloids?
(1) Si, Ge, Po, Pb
(3) Si, P, S, Cl
(2) As, Bi, Br, Kr
(4) Po, Sb, I, Xe
Reaction Coordinate
Reaction Coordinate
(2)
(4)
[OVER]
39 A chemist performs the same tests on two homogeneous white crystalline solids, A and B. The results are
shown in the table below.
Solid A
Solid B
Melting Point
High, 801°C
Low, decomposes
at 186°C
Solubility in H2O
(grams per 100.0 g H2O at 0°C)
35.7
3.2
Electrical Conductivity
(in aqueous solution)
Good conductor
Nonconductor
The results of these tests suggest that
(1) both solids contain only ionic bonds
(2) both solids contain only covalent bonds
(3) solid A contains only covalent bonds and solid B contains only ionic bonds
(4) solid A contains only ionic bonds and solid B contains only covalent bonds
43 A student intended to make a salt solution with
a concentration of 10.0 grams of solute per liter
of solution. When the student’s solution was
analyzed, it was found to contain 8.90 grams of
solute per liter of solution. What was the percent error in the concentration of the solution?
(1) 1.10%
(3) 11.0%
(2) 8.90%
(4) 18.9%
40 Solubility data for four different salts in water at
60°C are shown in the table below.
Salt
Solubility in Water at 60°C
A
10 grams / 50 grams H2O
B
20 grams / 60 grams H2O
C
30 grams / 120 grams H2O
D
40 grams/ 80 grams H2O
44 What is the molarity of a solution of NaOH if
2 liters of the solution contains 4 moles of NaOH?
(1) 0.5 M
(3) 8 M
(2) 2 M
(4) 80 M
Which salt is most soluble at 60°C?
(1) A
(2) B
(3) C
(4) D
45 A gas occupies a volume of 40.0 milliliters at
20°C. If the volume is increased to 80.0 milliliters at constant pressure, the resulting temperature will be equal to
41 Which phase change represents a decrease in
entropy?
(1) solid to liquid
(3) liquid to gas
(2) gas to liquid
(4) solid to gas
42 Given the equation:
2 C2H2(g) + 5 O2(g) → 4 CO2(g) + 2 H2O(g)
P.S./Chem.–Jan. ’03
80.0 mL
40.0 mL
(3) 293 K ×
80.0 mL
40.0 mL
(2) 20°C ×
40.0 mL
80.0 mL
(4) 293 K ×
40.0 mL
80.0 mL
46 According to Reference Table J, which of these
metals will react most readily with 1.0 M HCl to
produce H2(g)?
(1) Ca
(3) Mg
(2) K
(4) Zn
How many moles of oxygen are required to
react completely with 1.0 mole of C2H2?
(1) 2.5
(2) 2.0
(1) 20°C ×
(3) 5.0
(4) 10
[6]
47 The graph below represents the heating curve of a substance that starts as a solid below its freezing point.
•
Temperature (°C)
120
90
•
60
•
•
•
30 •
Time (minutes)
What is the melting point of this substance?
(1) 30°C
(2) 55°C
50 Given the system at equilibrium:
N2O4(g) + 58.1 kJ
2 NO2(g)
48 Given the unbalanced equation:
__Fe2O3 + __CO → __Fe + __CO2
When the equation is correctly balanced using
the smallest whole-number coefficients, what is
the coefficient of CO?
(1) 1
(2) 2
What will be the result of an increase in temperature at constant pressure?
(1) The equilibrium will shift to the left, and the
concentration of NO2(g) will decrease.
(2) The equilibrium will shift to the left, and the
concentration of NO2(g) will increase.
(3) The equilibrium will shift to the right, and
the concentration of NO2(g) will decrease.
(4) The equilibrium will shift to the right, and
the concentration of NO2(g) will increase.
(3) 3
(4) 4
49 Which type of organic compound is represented
by the structural formula shown below?
H
(1) aldehyde
(2) alcohol
P.S./Chem.–Jan. ’03
H
H
H
C
C
C
H
OH H
(3) 90°C
(4) 120°C
H
(3) ether
(4) ester
[7]
[OVER]
Part B–2
Answer all questions in this part.
Directions (51–61): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
51 In the boxes provided in your answer booklet:
a Draw two different compounds, one in each box, using the representations for atoms
of element X and element Z given below.
[1]
Atom of element X =
Atom of element Z =
b Draw a mixture of these two compounds.
[1]
•°
52 At equilibrium, nitrogen, hydrogen, and ammonia gases form a mixture in a sealed
container. The data table below gives some characteristics of these substances.
Data Table
Gas
Boiling Point
Melting Point
Solubility in Water
Nitrogen
–196°C
–210°C
insoluble
Hydrogen
–252°C
–259°C
insoluble
Ammonia
–33°C
–78°C
soluble
Describe how to separate ammonia from hydrogen and nitrogen.
[1]
Base your answers to questions 53 through 55 on the diagram of a voltaic cell provided in your answer booklet
and on your knowledge of chemistry.
53 On the diagram provided in your answer booklet, indicate with one or more arrows
the direction of electron flow through the wire. [1]
54 Write an equation for the half-reaction that occurs at the zinc electrode.
55 Explain the function of the salt bridge.
[1]
[1]
56 Given the nuclear equation:
235U
92
91
1
+ 10n → 142
56Ba + 36Kr + 3 0n + energy
a State the type of nuclear reaction represented by the equation. [1]
b The sum of the masses of the products is slightly less than the sum of the masses of
the reactants. Explain this loss of mass. [1]
c This process releases greater energy than an ordinary chemical reaction does. Name
another type of nuclear reaction that releases greater energy than an ordinary chemical reaction. [1]
P.S./Chem.–Jan. ’03
[8]
Base your answers to questions 57 through 60 on the information below.
Each molecule listed below is formed by sharing electrons between atoms when the
atoms within the molecule are bonded together.
Molecule A: Cl2
Molecule B: CCl4
Molecule C: NH3
57 In the box provided in your answer booklet, draw the electron-dot (Lewis) structure
for the NH3 molecule. [1]
58 Explain why CCl4 is classified as a nonpolar molecule.
[1]
59 Explain why NH3 has stronger intermolecular forces of attraction than Cl2.
[1]
60 Explain how the bonding in KCl is different from the bonding in molecules A, B, and C. [1]
61 How is the bonding between carbon atoms different in unsaturated hydrocarbons and
saturated hydrocarbons? [1]
P.S./Chem.–Jan. ’03
[9]
[OVER]
Part C
Answer all questions in this part.
Directions (62–74): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 62 through 64 on the information and diagram below.
One model of the atom states that atoms are tiny particles composed of a uniform mixture of positive and negative charges. Scientists conducted an experiment where alpha particles were aimed at a thin layer of gold atoms.
Most of the alpha particles passed directly through the gold atoms. A few alpha particles
were deflected from their straight-line paths. An illustration of the experiment is shown
below.
Alpha
particles
Deflected
alpha
particle
Gold
atoms
62 Most of the alpha particles passed directly through the gold atoms undisturbed. What
does this evidence suggest about the structure of the gold atoms? [1]
63 A few of the alpha particles were deflected. What does this evidence suggest about the
structure of the gold atoms? [1]
64 How should the original model be revised based on the results of this experiment?
P.S./Chem.–Jan. ’03
[10]
[1]
Base your answers to questions 65 through 67 on the information below.
When cola, a type of soda pop, is manufactured, CO2(g) is dissolved in it.
65 A capped bottle of cola contains CO2(g) under high pressure. When the cap is removed,
how does pressure affect the solubility of the dissolved CO2(g)? [1]
66 A glass of cold cola is left to stand 5 minutes at room temperature. How does temperature affect the solubility of the CO2(g)? [1]
67 a In the space provided in your answer booklet, draw a set of axes and label one of them
“Solubility” and the other “Temperature.” [1]
b Draw a line to indicate the solubility of CO2(g) versus temperature on the axes drawn
in part a. [1]
Base your answers to questions 68 through 70 on the graph below, which shows the vapor pressure curves
for liquids A and B.
800
700
Pressure (mm Hg)
600
500
400
A
300
B
200
100
0
0 10 20 30 40 50 60 70 80 90 100 110 120
Temperature (°C)
68 What is the vapor pressure of liquid A at 70°C? Your answer must include correct units.
[2]
69 At what temperature does liquid B have the same vapor pressure as liquid A at 70°C?
Your answer must include correct units.
[2]
70 Which liquid will evaporate more rapidly? Explain your answer in terms of intermolecular forces. [2]
P.S./Chem.–Jan. ’03
[11]
[OVER]
Base your answers to question 71 through 74 on the information and data table below.
A titration setup was used to determine the unknown molar concentration of a solution
of NaOH. A 1.2 M HCl solution was used as the titration standard. The following data were
collected.
Trial 1
Trial 2
Trial 3
Trial 4
Amount of HCI
Standard Used
10.0 mL
10.0 mL
10.0 mL
10.0 mL
Initial NaOH
Buret Reading
0.0 mL
12.2 mL
23.2 mL
35.2 mL
Final NaOH
Buret Reading
12.2 mL
23.2 mL
35.2 mL
47.7 mL
71 Calculate the volume of NaOH solution used to neutralize 10.0 mL of the standard HCl
solution in trial 3. Show your work. [2]
72 According to Reference Table M, what indicator would be most appropriate in determining the end point of this titration? Give one reason for choosing this indicator. [2]
73 Calculate the average molarity of the unknown NaOH solution for all four trials. Your
answer must include the correct number of significant figures and correct units.
[3]
74 Explain why it is better to use the average data from multiple trials rather than the data
from a single trial to calculate the results of the titration. [1]
P.S./Chem.–Jan. ’03
[12]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Wednesday, January 29, 2003 — 9:15 a.m. to 12:15 p.m., only
Student
ANSWER SHEET
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sex:
Teacher
..............................................
■ Male ■ Female Grade
...........
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
The University of the State of New York
PHYSICAL SETTING
CHEMISTRY
Wednesday, January 29, 2003 — 9:15 a.m. to 12:15 p.m., only
ANSWER BOOKLET
Student . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A
30
B–1
20
B–2
14
C
21
Student’s
Score
■ Male
Sex: ■ Female
Teacher . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maximum
Score
Part
REGENTS HIGH SCHOOL EXAMINATION
Grade . . . . . . . . .
Answer all questions in Part B–2 and Part C. Record your answers
in this booklet.
Total Written Test Score
(Maximum Raw Score: 85)
Final Score
(from conversion chart)
Raters’ Initials:
Rater 1 . . . . . . . . . . Rater 2 . . . . . . . . . . .
For Raters
Only
Part B–2
51 a
51a
b
b
52
52
[a]
[OVER]
For Raters
Only
Voltaic Cell
53
Wire
V
Voltmeter
Wire
Salt
bridge
Zinc
strip
Electrolyte
Copper
strip
53
Electrolyte
54
54
55
55
56 a
56a
b
b
c
c
57
57
58
58
[b]
For Raters
Only
59
59
60
60
61
61
Total Score
for Part B–2
Part C
62
62
63
63
64
64
65
65
66
66
[c]
[OVER]
For Raters
Only
67 a and b
67a
b
68
68
69
69
70 Liquid:
Explanation:
70
71
71
mL
72 Indicator:
Reason:
72
73
73
74
74
[d]
Total Score for Part C
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Tuesday, June 24, 2003 — 9:15 a.m. to 12:15 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for your use while taking this examination.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
Part A
Answer all questions in this part.
Directions (1–35): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
7 Alpha particles are emitted during the radioactive decay of
(1) carbon-14
(3) calcium-37
(2) neon-19
(4) radon-222
1 The atomic number of an atom is always equal
to the number of its
(1) protons, only
(2) neutrons, only
(3) protons plus neutrons
(4) protons plus electrons
8 Which is an empirical formula?
(1) P2O5
(3) C2H4
(2) P4O6
(4) C3H6
2 Which subatomic particle has no charge?
(1) alpha particle
(3) neutron
(2) beta particle
(4) electron
9 Which substance can be decomposed by a
chemical change?
(1) Co
(3) Cr
(2) CO
(4) Cu
3 When the electrons of an excited atom return to
a lower energy state, the energy emitted can
result in the production of
(1) alpha particles
(3) protons
(2) isotopes
(4) spectra
10 The percent by mass of calcium in the compound
calcium sulfate (CaSO4) is approximately
(1) 15%
(3) 34%
(2) 29%
(4) 47%
4 The atomic mass of an element is calculated
using the
(1) atomic number and the ratios of its naturally
occurring isotopes
(2) atomic number and the half-lives of each of
its isotopes
(3) masses and the ratios of its naturally occurring isotopes
(4) masses and the half-lives of each of its isotopes
11 What is represented by the dots in a Lewis
electron-dot diagram of an atom of an element
in Period 2 of the Periodic Table?
(1) the number of neutrons in the atom
(2) the number of protons in the atom
(3) the number of valence electrons in the atom
(4) the total number of electrons in the atom
5 The region that is the most probable location of
an electron in an atom is
(1) the nucleus
(3) the excited state
(2) an orbital
(4) an ion
12 Which type of chemical bond is formed
between two atoms of bromine?
(1) metallic
(3) ionic
(2) hydrogen
(4) covalent
6 Which is a property of most nonmetallic solids?
(1) high thermal conductivity
(2) high electrical conductivity
(3) brittleness
(4) malleability
P.S./Chem.–June ’03
13
[2]
Which of these formulas contains the most polar
bond?
(1) H–Br
(3) H–F
(2) H–Cl
(4) H–I
14 According to Table F, which of these salts is
least soluble in water?
(1) LiCl
(3) FeCl2
(2) RbCl
(4) PbCl2
22 Which statement correctly describes an
endothermic chemical reaction?
(1) The products have higher potential energy
than the reactants, and the ∆H is negative.
(2) The products have higher potential energy
than the reactants, and the ∆H is positive.
(3) The products have lower potential energy
than the reactants, and the ∆H is negative.
(4) The products have lower potential energy
than the reactants, and the ∆H is positive.
15 Which of these terms refers to matter that could
be heterogeneous?
(1) element
(3) compound
(2) mixture
(4) solution
23 At standard pressure when NaCl is added to
water, the solution will have a
(1) higher freezing point and a lower boiling
point than water
(2) higher freezing point and a higher boiling
point than water
(3) lower freezing point and a higher boiling
point than water
(4) lower freezing point and a lower boiling
point than water
16 In which material are the particles arranged in a
regular geometric pattern?
(3) H2O()
(1) CO2(g)
(2) NaCl(aq)
(4) C12H22O11(s)
17 Which change is exothermic?
(1) freezing of water
(2) melting of iron
(3) vaporization of ethanol
(4) sublimation of iodine
24 Which element has atoms that can form single,
double, and triple covalent bonds with other
atoms of the same element?
(1) hydrogen
(3) fluorine
(2) oxygen
(4) carbon
18 Which type of change must occur to form a
compound?
(1) chemical
(3) nuclear
(2) physical
(4) phase
25 Which compound is an isomer of pentane?
(1) butane
(3) methyl butane
(2) propane
(4) methyl propane
19 Which formula correctly represents the composition of iron (III) oxide?
(3) Fe3O
(1) FeO3
(2) Fe2O3
(4) Fe3O2
26 In which substance does chlorine have an
oxidation number of +1?
(1) Cl2
(3) HClO
(2) HCl
(4) HClO2
20 Given the reaction:
PbCl2(aq) + Na2CrO4(aq) →
PbCrO4(s) + 2 NaCl(aq)
27 Which statement is true for any electrochemical
cell?
(1) Oxidation occurs at the anode, only.
(2) Reduction occurs at the anode, only.
(3) Oxidation occurs at both the anode and the
cathode.
(4) Reduction occurs at both the anode and the
cathode.
What is the total number of moles of NaCl
formed when 2 moles of Na2CrO4 react completely?
(1) 1 mole
(2) 2 moles
(3) 3 moles
(4) 4 moles
21 Which hydrocarbon is saturated?
(1) propene
(3) butene
(2) ethyne
(4) heptane
P.S./Chem.–June ’03
[3]
[OVER]
32 Which type of radioactive emission has a positive charge and weak penetrating power?
(1) alpha particle
(3) gamma ray
(2) beta particle
(4) neutron
28 Given the equation:
2 Al + 3 Cu2+ → 2 Al3+ + 3 Cu
The reduction half-reaction is
(1) Al → Al3+ + 3e–
(2) Cu2+ + 2e– → Cu
(3) Al + 3e– → Al3+
(4) Cu2+ → Cu + 2e–
33 Which substance contains metallic bonds?
(1) Hg()
(3) NaCl(s)
(2) H2O()
(4) C6H12O6(s)
29 Which 0.1 M solution contains an electrolyte?
(3) CH3OH(aq)
(1) C6H12O6(aq)
(2) CH3COOH(aq)
(4) CH3OCH3(aq)
34 What is the name of the process in which the
nucleus of an atom of one element is changed
into the nucleus of an atom of a different element?
(1) decomposition
(3) substitution
(2) transmutation
(4) reduction
30 Which equation represents a neutralization
reaction?
(1) Na2CO3 + CaCl2 → 2 NaCl + CaCO3
(2) Ni(NO3)2 + H2S → NiS + 2 HNO3
(3) NaCl + AgNO3 → AgCl + NaNO3
(4) H2SO4 + Mg(OH)2 → MgSO4 + 2 H2O
Note that question 35 has only three choices.
35 A catalyst is added to a system at equilibrium. If
the temperature remains constant, the activation energy of the forward reaction
(1) decreases
(2) increases
(3) remains the same
31 An Arrhenius acid has
(1) only hydroxide ions in solution
(2) only hydrogen ions in solution
(3) hydrogen ions as the only positive ions in
solution
(4) hydrogen ions as the only negative ions in
solution
P.S./Chem.–June ’03
[4]
Part B–1
Answer all questions in this part.
Directions (36–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
43 The potential energy diagram below represents
a reaction.
36 The nucleus of an atom of K-42 contains
(1) 19 protons and 23 neutrons
(2) 19 protons and 42 neutrons
(3) 20 protons and 19 neutrons
(4) 23 protons and 19 neutrons
Potential Energy
B
37 What is the total number of electrons in a
Cu+ ion?
(1) 28
(3) 30
(2) 29
(4) 36
38 Which list of elements is arranged in order of
increasing atomic radii?
(1) Li, Be, B, C
(3) Sc, Ti, V, Cr
(2) Sr, Ca, Mg, Be
(4) F, Cl, Br, I
C
A
D
Reaction Coordinate
Which arrow represents the activation energy of
the forward reaction?
(1) A
(2) B
39 Which isotope is most commonly used in the
radioactive dating of the remains of organic
materials?
(3) 32P
(1) 14C
16
(2) N
(4) 37K
(3) C
(4) D
44 Given the formulas of four organic compounds:
H H
O
(a) H C C C
40 According to Reference Table H, what is the
vapor pressure of propanone at 45°C?
(1) 22 kPa
(3) 70. kPa
(2) 33 kPa
(4) 98 kPa
H
H H
O
OH
H
H
H H
H
H
OH H
Which pair below contains an alcohol and an
acid?
(1) a and b
(2) a and c
42 Hexane (C6H14) and water do not form a solution.
Which statement explains this phenomenon?
(1) Hexane is polar and water is nonpolar.
(2) Hexane is ionic and water is polar.
(3) Hexane is nonpolar and water is polar.
(4) Hexane is nonpolar and water is ionic.
[5]
H
(d) H C C C H
H H
41 The freezing point of bromine is
(1) 539°C
(3) 7°C
(2) –539°C
(4) –7°C
H
(c) H C C C
H H
(b) H C C C
P.S./Chem.–June ’03
H O
(3) b and d
(4) c and d
[OVER]
45 Which type of reaction is represented by the equation below?
Note:
n and n are very large numbers equal to about 2000.
H
H
n
C
C
H
H
(1) esterification
(2) fermentation
V
Voltmeter
Salt
bridge
Pb(s) + Cu2 +(aq)
Cu(s)
1.0 M
Cu2+(aq)
H
H
n
Solution
Conductivity
Color with
Phenolphthalein
A
Good
Colorless
B
Poor
Colorless
C
Good
Pink
D
Poor
Pink
(1) A
(2) B
Pb2 +(aq) + Cu(s)
(3) C
(4) D
239
49 In the reaction 239
93Np → 94Pu + X, what does X
represent?
(1) a neutron
(3) an alpha particle
(2) a proton
(4) a beta particle
the Pb(s) to the Cu(s)
the Cu(s) to the Pb(s)
the Pb2+(aq) to the Pb(s)
the Cu2+(aq) to the Cu(s)
Note that question 50 has only three choices.
50 As carbon dioxide sublimes, its entropy
(1) decreases
(2) increases
(3) remains the same
47 Which ion has the same electron configuration
as an atom of He?
(3) Na+
(1) H–
2–
(2) O
(4) Ca2+
P.S./Chem.–June ’03
C
Based on the data table, which unknown solution could be 0.1 M NaOH?
When the switch is closed, electrons will flow
from
(1)
(2)
(3)
(4)
C
48 A student was given four unknown solutions.
Each solution was checked for conductivity and
tested with phenolphthalein. The results are
shown in the data table below.
Switch
1.0 M
Pb2+(aq)
H
(3) saponification
(4) polymerization
46 A diagram of a chemical cell and an equation are
shown below.
Pb(s)
H
[6]
Part B–2
Answer all questions in this part.
Directions (51–63): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 51 and 52 on the electron configuration table shown below.
Element
Electron
Configuration
X
2–8–8–2
Y
2–8–7–3
Z
2–8–8
51 What is the total number of valence electrons in an atom of electron configuration X? [1]
52 Which electron configuration represents the excited state of a calcium atom?
[1]
Base your answers to questions 53 and 54 on the information below.
Given: Samples of Na, Ar, As, Rb
53 Which two of the given elements have the most similar chemical properties?
54 Explain your answer in terms of the Periodic Table of the Elements.
[1]
[1]
Base your answers to questions 55 and 56 on the information below.
Diethyl ether is widely used as a solvent.
55 In the space provided in your answer booklet, draw the structural formula for diethyl
ether. [1]
56 In the space provided in your answer booklet, draw the structural formula for an
alcohol that is an isomer of diethyl ether. [1]
P.S./Chem.–June ’03
[7]
[OVER]
Base your answers to questions 57 and 58 on the information below.
Two chemistry students each combine a different metal with
hydrochloric acid. Student A uses zinc, and hydrogen gas is readily produced. Student B uses copper, and no hydrogen gas is produced.
57 State one chemical reason for the different results of students A and B.
[1]
58 Using Reference Table J, identify another metal that will react with hydrochloric acid
to yield hydrogen gas. [1]
59 Given the reaction between two different elements in the gaseous state:
+
+
Box A below represents a mixture of the two reactants before the reaction occurs.
The product of this reaction is a gas. In Box B provided in your answer booklet, draw
the system after the reaction has gone to completion, based on the Law of
Conservation of Matter. [2]
Box A
System Before Reaction
60 As a neutral sulfur atom gains two electrons, what happens to the radius of the atom? [1]
61 After a neutral sulfur atom gains two electrons, what is the resulting charge of the ion? [1]
62 a In the space provided in your answer booklet, calculate the heat released when
25.0 grams of water freezes at 0°C. Show all work. [1]
b Record your answer with an appropriate unit. [1]
63 State one difference between voltaic cells and electrolytic cells. Include information
about both types of cells in your answer. [1]
P.S./Chem.–June ’03
[8]
Part C
Answer all questions in this part.
Directions (64–79): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 64 and 65 on the diagram below, which shows a piston confining a gas in a
cylinder.
64 Using the set of axes provided in your answer booklet, sketch the general relationship
between the pressure and the volume of an ideal gas at constant temperature. [1]
65 The gas volume in the cylinder is 6.2 milliliters and its pressure is 1.4 atmospheres. The
piston is then pushed in until the gas volume is 3.1 milliliters while the temperature
remains constant.
a In the space provided in your answer booklet, calculate the pressure, in atmospheres,
after the change in volume. Show all work. [1]
b Record your answer. [1]
66 A student recorded the following buret readings during a titration of a base with an acid:
Standard 0.100 M HCl
Unknown KOH
Initial reading
9.08 mL
0.55 mL
Final reading
19.09 mL
5.56 mL
a In the space provided in your answer booklet, calculate the molarity of the KOH.
Show all work. [1]
b Record your answer to the correct number of significant figures. [1]
67 John Dalton was an English scientist who proposed that atoms were hard, indivisible
spheres. In the modern model, the atom has a different internal structure.
a Identify one experiment that led scientists to develop the modern model of the atom. [1]
b Describe this experiment. [1]
c State one conclusion about the internal structure of the atom, based on this experiment. [1]
P.S./Chem.–June ’03
[9]
[OVER]
Base your answers to questions 68 through 73 on the information below and on your knowledge of chemistry.
Nuclear Waste Storage Plan for Yucca Mountain
In 1978, the U.S. Department of Energy began a study of Yucca Mountain which is
located 90 miles from Las Vegas, Nevada. The study was to determine if Yucca Mountain
would be suitable for a long-term burial site for high-level radioactive waste. A threedimensional (3-D) computer scale model of the site was used to simulate the Yucca
Mountain area. The computer model study for Yucca Mountain included such variables as:
the possibility of earthquakes, predicted water flow through the mountain, increased rainfall due to climate changes, radioactive leakage from the waste containers, and increased
temperatures from the buried waste within the containers.
The containers that will be used to store the radioactive waste are designed to last 10,000
years. Within the 10,000-year time period, cesium and strontium, the most powerful
radioactive emitters, would have decayed. Other isotopes found in the waste would decay
more slowly, but are not powerful radioactive emitters.
In 1998, scientists discovered that the compressed volcanic ash making up Yucca Mountain
was full of cracks. Because of the arid climate, scientists assumed that rainwater would move
through the cracks at a slow rate. However, when radioactive chlorine-36 was found in rock
samples at levels halfway through the mountain, it was clear that rainwater had moved
quickly down through Yucca Mountain. It was only 50 years earlier when this chlorine-36
isotope had contaminated rainwater during atmospheric testing of the atom bomb.
Some opponents of the Yucca Mountain plan believe that the uncertainties related to the
many variables of the computer model result in limited reliability of its predictions.
However, advocates of the plan believe it is safer to replace the numerous existing radioactive burial sites around the United States with the one site at Yucca Mountain. Other
opponents of the plan believe that transporting the radioactive waste to Yucca Mountain
from the existing 131 burial sites creates too much danger to the United States. In 2002,
after years of political debate, a final legislative vote approved the development of Yucca
Mountain to replace the existing 131 burial sites.
68 State one uncertainty in the computer model that limits the reliability of this
computer model. [1]
69 Scientists assume that a manufacturing defect would cause at least one of the waste
containers stored in the Yucca Mountain repository to leak within the first 1,000 years.
State one possible effect such a leak could have on the environment near Yucca
Mountain. [1]
70 State one risk associated with leaving radioactive waste in the 131 sites around the
country where it is presently stored. [1]
71 If a sample of cesium-137 is stored in a waste container in Yucca Mountain, how much
time must elapse until only
1
32
of the original sample remains unchanged?
[1]
72 The information states “Within the 10,000-year time period, cesium and strontium, the
most powerful radioactive emitters, would have decayed.” Use information from
Reference Table N to support this statement. [1]
73 Why is water flow a crucial factor in deciding whether Yucca Mountain is a suitable
burial site? [1]
P.S./Chem.–June ’03
[10]
Base your answers to questions 74 through 76 on the information below.
A student wishes to investigate how the reaction rate changes with a change in concentration of HCl(aq).
Given the reaction: Zn(s) + HCl(aq) → H2(g) + ZnCl2(aq)
74 Identify the independent variable in this investigation.
[1]
75 Identify one other variable that might affect the rate and should be held constant
during this investigation. [1]
76 Describe the effect of increasing the concentration of HCl(aq) on the reaction rate and
justify your response in terms of collision theory. [1]
Base your answers to questions 77 through 79 on the information below.
A truck carrying concentrated nitric acid overturns and spills its contents. The acid drains
into a nearby pond. The pH of the pond water was 8.0 before the spill. After the spill, the
pond water is 1,000 times more acidic.
77 Name an ion in the pond water that has increased in concentration due to this spill. [1]
78 What is the new pH of the pond water after the spill?
79 What color would bromthymol blue be at this new pH?
P.S./Chem.–June ’03
[11]
[1]
[1]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Tuesday, June 24, 2003 — 9:15 a.m. to 12:15 p.m., only
Student
ANSWER SHEET
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sex:
Teacher
..............................................
■ Male ■ Female Grade
...........
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
13 . . . . . . . . . . . .
25 . . . . . . . . . . .
36 . . . . . . . . . . . .
44 . . . . . . . . . . . .
2 ............
14 . . . . . . . . . . . .
26 . . . . . . . . . . .
37 . . . . . . . . . . . .
45 . . . . . . . . . . . .
3 ............
15 . . . . . . . . . . . .
27 . . . . . . . . . . .
38 . . . . . . . . . . . .
46 . . . . . . . . . . . .
4 ............
16 . . . . . . . . . . . .
28 . . . . . . . . . . .
39 . . . . . . . . . . . .
47 . . . . . . . . . . . .
5 ............
17 . . . . . . . . . . . .
29 . . . . . . . . . . .
40 . . . . . . . . . . . .
48 . . . . . . . . . . . .
6 ............
18 . . . . . . . . . . . .
30 . . . . . . . . . . .
41 . . . . . . . . . . . .
49 . . . . . . . . . . . .
7 ............
19 . . . . . . . . . . . .
31 . . . . . . . . . . .
42 . . . . . . . . . . . .
50 . . . . . . . . . . . .
8 ............
20 . . . . . . . . . . . .
32 . . . . . . . . . . .
43 . . . . . . . . . . . .
Part B–1 Score
9 ............
21 . . . . . . . . . . . .
33 . . . . . . . . . . .
10 . . . . . . . . . . . .
22 . . . . . . . . . . . .
34 . . . . . . . . . . .
11 . . . . . . . . . . . .
23 . . . . . . . . . . . .
35 . . . . . . . . . . .
12 . . . . . . . . . . . .
24 . . . . . . . . . . . .
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Wednesday, August 13, 2003 — 12:30 to 3:30 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for your use while taking this examination.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
Part A
Answer all questions in this part.
Directions (1–35): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
7 Which element is a solid at STP?
(1) H2
(3) N2
(2) I2
(4) O2
1 Which electron transition represents a gain of
energy?
(1) from 2nd to 3rd shell
(2) from 2nd to 1st shell
(3) from 3rd to 2nd shell
(4) from 3rd to 1st shell
8 In which compound is the percent by mass of
oxygen greatest?
(1) BeO
(3) CaO
(2) MgO
(4) SrO
2 Which particles are found in the nucleus of an
atom?
(1) electrons, only
(2) neutrons, only
(3) protons and electrons
(4) protons and neutrons
9 Based on Reference Table F, which of these
salts is the best electrolyte?
(1) sodium nitrate
(2) magnesium carbonate
(3) silver chloride
(4) barium sulfate
3 What is the total number of valence electrons in
an atom of sulfur in the ground state?
(1) 6
(3) 3
(2) 8
(4) 4
10 What is conserved during a chemical reaction?
(1) mass, only
(2) charge, only
(3) both mass and charge
(4) neither mass nor charge
4 An electron has a charge of
(1) –1 and the same mass as a proton
(2) +1 and the same mass as a proton
(3) –1 and a smaller mass than a proton
(4) +1 and a smaller mass than a proton
11 Which type of bond is formed when electrons
are transferred from one atom to another?
(1) covalent
(3) hydrogen
(2) ionic
(4) metallic
5 The elements in the Periodic Table are arranged
in order of increasing
(1) atomic number
(2) atomic radius
(3) mass number
(4) neutron number
12 Which Lewis electron-dot structure is drawn
correctly for the atom it represents?
6 What is the correct IUPAC name for the compound NH4Cl?
(1) nitrogen chloride
(2) nitrogen chlorate
(3) ammonium chloride
(4) ammonium chlorate
P.S./Chem.–Aug. ’03
[2]
(1)
N
(3)
O
(2)
F
(4)
Ne
13 What occurs when an atom of chlorine forms a
chloride ion?
(1) The chlorine atom gains an electron, and its
radius becomes smaller.
(2) The chlorine atom gains an electron, and its
radius becomes larger.
(3) The chlorine atom loses an electron, and its
radius becomes smaller.
(4) The chlorine atom loses an electron, and its
radius becomes larger.
20 At the same temperature and pressure, 1.0 liter
of CO(g) and 1.0 liter of CO2(g) have
(1) equal masses and the same number of molecules
(2) different masses and a different number of
molecules
(3) equal volumes and the same number of molecules
(4) different volumes and a different number of
molecules
14 Which substance can not be decomposed by a
chemical change?
(1) Ne
(3) HF
(2) N2O
(4) H2O
21 Which type of reaction occurs when nonmetal
atoms become negative nonmetal ions?
(1) oxidation
(3) substitution
(2) reduction
(4) condensation
15 Which of these substances has the strongest
intermolecular forces?
(3) H2Se
(1) H2O
(2) H2S
(4) H2Te
22 Given the reaction:
H2O
AgCl(s)
Once equilibrium is reached, which statement is
accurate?
16 A real gas behaves more like an ideal gas when
the gas molecules are
(1) close and have strong attractive forces between
them
(2) close and have weak attractive forces between
them
(3) far apart and have strong attractive forces
between them
(4) far apart and have weak attractive forces
between them
(1) The concentration of Ag+(aq) is greater than
the concentration of Cl–(aq).
(2) The AgCl(s) will be completely consumed.
(3) The rates of the forward and reverse reactions are equal.
(4) The entropy of the forward reaction will
continue to decrease.
23 Which structural formula correctly represents a
hydrocarbon molecule?
H
_
(1)
H
_H
H _ C _ C __
O
H
(3)
H
_ _
C C_
H
H
H
_
H
19 In which group of the Periodic Table do most of
the elements exhibit both positive and negative
oxidation states?
(1) 17
(3) 12
(2) 2
(4) 7
_
(2)
[3]
H
_ _
_
C C_
_
18 Which of these contains only one substance?
(1) distilled water
(3) saltwater
(2) sugar water
(4) rainwater
H
_
H
_ C_
C
_
_
H
H
_
17 Which phase change is an exothermic process?
(1) CO2(s) → CO2(g)
(3) Cu(s) → Cu()
(2) NH3(g) → NH3() (4) Hg() → Hg(g)
P.S./Chem.–Aug. ’03
Ag+(aq) + Cl–(aq)
_
H
(4)
[OVER]
24 Given the structural formulas for two organic compounds:
_
_
H
_
_
_
_
_
H H
_
_
_
and
_
H O
H
H _ C _ C _ C _ O_ C _H
H
_
_
_
_
H
_
H H O
H _ C _ C _ C _ C _ OH
H
H
H
The differences in their physical and chemical properties are primarily due to their
different
(1) number of carbon atoms
(3) molecular masses
(2) number of hydrogen atoms
(4) functional groups
28 When the pH of a solution changes from a pH of 5
to a pH of 3, the hydronium ion concentration is
(1) 0.01 of the original content
(2) 0.1 of the original content
(3) 10 times the original content
(4) 100 times the original content
25 Which structural formula represents a molecule
that is not an isomer of pentane?
_
H
_
H
H
_
_
H
H_ C_ C_ C_ C_H
_
_
_
_
_
_
_
H
_ C_ H
H
H
H
_
_
_
H H H H
(1)
_
_
H
_
_
H H H H H
_
H C _ C _ C _ C __ C __H
29 A sample of Ca(OH)2 is considered to be an
Arrhenius base because it dissolves in water to
yield
(1) Ca2+ ions as the only positive ions in solution
(2) H3O+ ions as the only positive ions in solution
–
(3) OH ions as the only negative ions in solution
–
(4) H ions as the only negative ions in solution
H
(3)
H
_
_
H_ C_ H
H
H
_
_
_
H C C C_ H
_
_
_
_
H
_ C_ H
H
H
_
H
(2)
H H
C
H
H
C
C
H
H
H C C H
H
30 Which reaction occurs when hydrogen ions
react with hydroxide ions to form water?
(1) substitution
(3) ionization
(2) saponification
(4) neutralization
H
(4)
26 The bonds in the compound MgSO4 can be
described as
(1) ionic, only
(2) covalent, only
(3) both ionic and covalent
(4) neither ionic nor covalent
31 Which of these types of nuclear radiation has
the greatest penetrating power?
(1) alpha
(3) neutron
(2) beta
(4) gamma
32 Alpha particles and beta particles differ in
(1) mass, only
(2) charge, only
(3) both mass and charge
(4) neither mass nor charge
27 Given the reaction:
Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g)
Which statement correctly describes what occurs
when this reaction takes place in a closed system?
(1)
(2)
(3)
(4)
Atoms of Zn(s) lose electrons and are oxidized.
Atoms of Zn(s) gain electrons and are reduced.
There is a net loss of mass.
There is a net gain of mass.
P.S./Chem.–Aug. ’03
[4]
Note that question 35 has only three choices.
33 Given the nuclear reaction:
60 Co
27
→
0
–1e
35 In most aqueous reactions as temperature
increases, the effectiveness of collisions between
reacting particles
(1) decreases
(2) increases
(3) remains the same
+ 60
28 Ni
This reaction is an example of
(1)
(2)
(3)
(4)
fission
fusion
artificial transmutation
natural transmutation
34 As two chlorine atoms combine to form a molecule, energy is
(1) absorbed
(3) created
(2) released
(4) destroyed
P.S./Chem.–Aug. ’03
[5]
[OVER]
Part B–1
Answer all questions in this part.
Directions (36–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
41 Which equation represents a double replacement reaction?
(1) 2 Na + 2 H2O → 2 NaOH + H2
(2) CaCO3 → CaO + CO2
(3) LiOH + HCl → LiCl + H2O
(4) CH4 + 2 O2 → CO2 + 2 H2O
36 What is the total number of neutrons in an atom
of an element that has a mass number of 19 and
an atomic number of 9?
(1) 9
(3) 19
(2) 10
(4) 28
37 The element in Period 4 and Group 1 of the
Periodic Table would be classified as a
(1) metal
(3) nonmetal
(2) metalloid
(4) noble gas
42 What is the molecular formula of a compound
that has a molecular mass of 54 and the empirical formula C2H3?
(3) C6H9
(1) C2H3
(2) C4H6
(4) C8H12
38 As the elements in Period 2 of the Periodic Table
are considered in succession from left to right,
there is a decrease in atomic radius with increasing atomic number. This may best be explained
by the fact that the
(1) number of protons increases, and the number of shells of electrons remains the same
(2) number of protons increases, and the number of shells of electrons increases
(3) number of protons decreases, and the number of shells of electrons remains the same
(4) number of protons decreases, and the number of shells of electrons increases
43 Given the diagrams X, Y, and Z below:
X
Y
Z
Key
Atom of element A =
39 Given the balanced equation:
Atom of element B =
2 C4H10(g) + 13 O2(g) → 8 CO2(g) + 10 H2O(g)
What is the total number of moles of O2(g) that
must react completely with 5.00 moles of
C4H10(g)?
(1) 10.0
(2) 20.0
Which diagram or diagrams represent a mixture
of elements A and B?
(1) X, only
(2) Z, only
(3) 26.5
(4) 32.5
44 Which is an electron configuration for an atom
of chlorine in the excited state?
(1) 2–8–7
(3) 2–8–6–1
(2) 2–8–8
(4) 2–8–7–1
40 Which particle has the same electron configuration as a potassium ion?
(1) fluoride ion
(3) neon atom
(2) sodium ion
(4) argon atom
P.S./Chem.–Aug. ’03
(3) X and Y
(4) X and Z
[6]
45 Based on the nature of the reactants in each of
the equations below, which reaction at 25°C will
occur at the fastest rate?
(1) C(s) + O2(g) → CO2(g)
(2) NaOH(aq) + HCl(aq) →
NaCl(aq) + H2O()
(3) CH3OH() + CH3COOH() →
CH3COOCH3(aq) + H2O()
(4) CaCO3(s) → CaO(s) + CO2(g)
48 A voltaic cell differs from an electrolytic cell in
that in a voltaic cell
(1) energy is produced when the reaction occurs
(2) energy is required for the reaction to occur
(3) both oxidation and reduction occur
(4) neither oxidation nor reduction occurs
49 What is the purpose of the salt bridge in a voltaic
cell?
(1) It blocks the flow of electrons.
(2) It blocks the flow of positive and negative ions.
(3) It is a path for the flow of electrons.
(4) It is a path for the flow of positive and negative ions.
46 Given the reaction at equilibrium:
A(g) + B(g)
AB(g) + heat
The concentration of A(g) can be increased by
(1)
(2)
(3)
(4)
50 According to Reference Table N, which radio1
active isotope will retain only one-eighth ( 8 ) its
original radioactive atoms after approximately
43 days?
(1) gold-198
(3) phosphorus-32
(2) iodine-131
(4) radon-222
lowering the temperature
adding a catalyst
increasing the concentration of AB(g)
increasing the concentration of B(g)
47 Which structural formula represents an alcohol?
H
H
O
H
C
C
C
H
H
H
H
H
C
H
H
C
C
C
H
H
H
P.S./Chem.–Aug. ’03
H
(3)
H
(2)
C
H
(1)
H
O
H
OH
H
C
O
C
H
OH
(4)
[7]
[OVER]
Part B–2
Answer all questions in this part.
Directions (51–62): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
51 Explain how a catalyst may increase the rate of a chemical reaction.
[1]
52 On the set of axes provided in your answer booklet, sketch the potential energy diagram
for an endothermic chemical reaction that shows the activation energy and the
potential energy of the reactants and the potential energy of the products. [2]
53 Given the reaction: Cl2 + 2 HBr → Br2 + 2 HCl
Write a correctly balanced reduction half-reaction for this equation.
[1]
Base your answers to questions 54 and 55 on the information below.
Given the unbalanced equation:
____ C6H12O6
enzyme
____ C2H5OH + ____ CO2
54 Balance the equation provided in your answer booklet, using the lowest whole-number
coefficients.
[1]
55 Identify the type of reaction represented.
[1]
Base your answers to questions 56 through 58 on the Reference Tables for Physical Setting/Chemistry.
56 Complete the data table provided in your answer booklet for the following Group 18
elements: He, Ne, Ar, Kr, Xe [1]
57 Using information from your data table in question 56, construct a line graph on the
grid provided in your answer booklet, following the directions below.
• Mark an appropriate scale on the axis labeled “First Ionization Energy (kJ/mol). ” [1]
• Plot the data from your data table. Circle each point and connect the points. [1]
Example:
58 Based on your graph in question 57, describe the trend in first ionization energy of
Group 18 elements as the atomic number increases. [1]
P.S./Chem.–Aug. ’03
[8]
Base your answers to questions 59 through 62 on the information below.
Given the heating curve where substance X starts as a solid below
its melting point and is heated uniformly:
F
Temperature (°C)
D
E
B
C
A
Time (minutes)
59 Identify the process that takes place during line segment DE of the heating curve.
60 Identify a line segment in which the average kinetic energy is increasing.
[1]
[1]
61 Using (•) to represent particles of substance X, draw at least five particles as they would
appear in the substance at point F. Use the box provided in your answer booklet. [1]
62 Describe, in terms of particle behavior or energy, what is happening to substance X
during line segment BC . [1]
P.S./Chem.–Aug. ’03
[9]
[OVER]
Part C
Answer all questions in this part.
Directions (63–78): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 63 and 64 on the diagram below, which shows bright-line spectra
of selected elements.
Bright-Line Spectra
Li
H
He
Na
Unknown
63 Identify the two elements in the unknown spectrum.
[2]
64 Explain how a bright-line spectrum is produced, in terms of excited state, energy
transitions, and ground state. [2]
65 The table below gives information about two isotopes of element X.
Isotope
Mass
Relative Abundance
X-10
10.01
19.91%
X-11
11.01
80.09%
Calculate the average atomic mass of element X.
• Show a correct numerical setup in the space provided in your answer booklet.
• Record your answer. [1]
• Express your answer to the correct number of significant figures. [1]
[1]
66 A student determines the density of zinc to be 7.56 grams per milliliter. If the
accepted density is 7.14 grams per milliliter, what is the student’s percent error?
• Show a correct numerical setup in the space provided in your answer booklet.
• Record your answer. [1]
P.S./Chem.–Aug. ’03
[10]
[1]
Base your answers to questions 67 through 69 on the information below.
Given the equation for the dissolving of sodium chloride in water:
NaCl(s)
H2O
Na+(aq) + Cl–(aq)
67 Describe what happens to entropy during this dissolving process.
[1]
68 Explain, in terms of particles, why NaCl(s) does not conduct electricity.
[1]
69 When NaCl(s) is added to water in a 250-milliliter beaker, the temperature of the
mixture is lower than the original temperature of the water. Describe this observation
in terms of heat flow. [1]
Base your answers to questions 70 through 74 on the article below, the Reference Tables for Physical
Setting/Chemistry, and your knowledge of chemistry.
In the 1920s, paint used to inscribe the numbers on watch dials was composed of a
luminescent (glow-in-the-dark) mixture. The powdered-paint base was a mixture of radium
salts and zinc sulfide. As the paint was mixed, the powdered base became airborne and
drifted throughout the workroom causing the contents of the workroom, including the
painters’ clothes and bodies, to glow in the dark.
The paint is luminescent because radiation from the radium salts strikes a scintillator. A
scintillator is a material that emits visible light in response to ionizing radiation. In watchdial paint, zinc sulfide acts as the scintillator.
Radium present in the radium salts decomposes spontaneously, emitting alpha
particles. These particles can cause damage to the body when they enter human tissue.
Alpha particles are especially harmful to the blood, liver, lungs, and spleen because they can
alter genetic information in the cells. Radium can be deposited in the bones because it
substitutes for calcium.
70 Write the notation for the alpha particles emitted by radium in the radium salts.
71 How can particles emitted from radioactive nuclei damage human tissue?
72 Why does radium substitute for calcium in bones?
[1]
74 Based on Reference Table F, describe the solubility of zinc sulfide in water.
[11]
[1]
[1]
73 Explain why zinc sulfide is used in luminescent paint.
P.S./Chem.–Aug. ’03
[1]
[1]
[OVER]
Base your answers to questions 75 through 78 on the article below and on your knowledge of chemistry.
Fizzies — A Splash from the Past
They’re baaack . . . a splash from the past! Fizzies instant sparkling drink tablets, popular in the 1950s and 1960s, are now back on the market. What sets them apart from other
powdered drinks is that they bubble and fizz when placed in water, forming an instant carbonated beverage.
The fizz in Fizzies is caused by bubbles of carbon dioxide (CO2) gas that are released
when the tablet is dropped into water. Careful observation reveals that these bubbles rise
to the surface because CO2 gas is much less dense than water. However, not all of the CO2
gas rises to the surface; some of it dissolves in the water. The dissolved CO2 can react with
water to form carbonic acid, H2CO3.
H2O( ) + CO2(aq)
H2CO3(aq)
The pH of the Fizzies drink registers between 5 and 6, showing that the resulting solution is clearly acidic. Carbonic acid is found in other carbonated beverages as well. One of
the ingredients on any soft drink label is carbonated water, which is another name for carbonic acid. However, in the production of soft drinks, the CO2 is pumped into the solution
under high pressure at the bottling plant.
— Brian Rohrig
Excerpted from “Fizzies—A Splash from the Past,”
Chem Matters, February 1998
75 What is the only positive ion in an aqueous solution of carbonic acid?
[1]
76 CO2 is pumped into the soft drink solution under high pressure. Why is high pressure
necessary? [1]
77 Describe the solubility of CO2 gas in water.
[1]
78 Explain your response to question 77 in terms of the molecular polarities of CO2(g) and
H2O(). [1]
P.S./Chem.–Aug. ’03
[12]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Wednesday, August 13, 2003 — 12:30 to 3:30 p.m., only
Student
ANSWER SHEET
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sex:
Teacher
..............................................
■ Male ■ Female Grade
...........
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
13 . . . . . . . . . . . .
25 . . . . . . . . . . .
36 . . . . . . . . . . . .
44 . . . . . . . . . . . .
2 ............
14 . . . . . . . . . . . .
26 . . . . . . . . . . .
37 . . . . . . . . . . . .
45 . . . . . . . . . . . .
3 ............
15 . . . . . . . . . . . .
27 . . . . . . . . . . .
38 . . . . . . . . . . . .
46 . . . . . . . . . . . .
4 ............
16 . . . . . . . . . . . .
28 . . . . . . . . . . .
39 . . . . . . . . . . . .
47 . . . . . . . . . . . .
5 ............
17 . . . . . . . . . . . .
29 . . . . . . . . . . .
40 . . . . . . . . . . . .
48 . . . . . . . . . . . .
6 ............
18 . . . . . . . . . . . .
30 . . . . . . . . . . .
41 . . . . . . . . . . . .
49 . . . . . . . . . . . .
7 ............
19 . . . . . . . . . . . .
31 . . . . . . . . . . .
42 . . . . . . . . . . . .
50 . . . . . . . . . . . .
8 ............
20 . . . . . . . . . . . .
32 . . . . . . . . . . .
43 . . . . . . . . . . . .
9 ............
21 . . . . . . . . . . . .
33 . . . . . . . . . . .
10 . . . . . . . . . . . .
22 . . . . . . . . . . . .
34 . . . . . . . . . . .
11 . . . . . . . . . . . .
23 . . . . . . . . . . . .
35 . . . . . . . . . . .
12 . . . . . . . . . . . .
24 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Wednesday, January 28, 2004 — 9:15 a.m. to 12:15 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for your use while taking this examination.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
Part A
Answer all questions in this part.
Directions (1–31): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
1 A neutral atom contains
11 electrons. The number
atom is
(1) 1
(3)
(2) 11
(4)
12 neutrons and
of protons in this
7 The bond between Br atoms in a Br2 molecule is
(1) ionic and is formed by the sharing of two
valence electrons
(2) ionic and is formed by the transfer of two
valence electrons
(3) covalent and is formed by the sharing of two
valence electrons
(4) covalent and is formed by the transfer of two
valence electrons
12
23
2 Isotopes of an element must have different
(1) atomic numbers
(2) mass numbers
(3) numbers of protons
(4) numbers of electrons
8 The amount of energy required to remove the
outermost electron from a gaseous atom in the
ground state is known as
(1) first ionization energy
(2) activation energy
(3) conductivity
(4) electronegativity
3 Which element is a noble gas?
(1) krypton
(3) antimony
(2) chlorine
(4) manganese
4 On the present Periodic Table of the Elements,
the elements are arranged according to increasing
(1) number of oxidation states
(2) number of neutrons
(3) atomic mass
(4) atomic number
9 What occurs when an atom of chlorine and an
atom of hydrogen become a molecule of hydrogen chloride?
(1) A chemical bond is broken and energy is
released.
(2) A chemical bond is broken and energy is
absorbed.
(3) A chemical bond is formed and energy is
released.
(4) A chemical bond is formed and energy is
absorbed.
5 What is a property of most metals?
(1) They tend to gain electrons easily when bonding.
(2) They tend to lose electrons easily when bonding.
(3) They are poor conductors of heat.
(4) They are poor conductors of electricity.
10 Which molecule is nonpolar?
(1) H2O
(3) CO
(4) CO2
(2) NH3
6 What is the correct formula for iron (III) phosphate?
(1) FeP
(3) FePO4
(2) Fe3P2
(4) Fe3(PO4)2
P.S./Chem.–Jan. ’04
11 Which must be a mixture of substances?
(1) solid
(3) gas
(2) liquid
(4) solution
[2]
17 Given the reaction at equilibrium:
12 A bottle of rubbing alcohol contains both
2-propanol and water. These liquids can be separated by the process of distillation because the
2-propanol and water
(1) have combined chemically and retain their
different boiling points
(2) have combined chemically and have the
same boiling point
(3) have combined physically and retain their
different boiling points
(4) have combined physically and have the same
boiling point
H2(g) + Br2(g)
The rate of the forward reaction is
(1)
(2)
(3)
(4)
14 Under which conditions does a real gas behave
most like an ideal gas?
(1) at low temperatures and high pressures
(2) at low temperatures and low pressures
(3) at high temperatures and high pressures
(4) at high temperatures and low pressures
19 All organic compounds must contain the element
(1) phosphorus
(3) carbon
(2) oxygen
(4) nitrogen
15 What is the IUPAC name of the compound with
the following structural formula?
20 Which of the following compounds has the
highest boiling point?
(1) H2O
(3) H2Se
(2) H2S
(4) H2Te
H O H H
H C C C C H
(1) propanone
(2) propanal
H H
21 The functional group —COOH is found in
(1) esters
(3) alcohols
(2) aldehydes
(4) organic acids
(3) butanone
(4) butanal
16 Which statement best explains the role of a
catalyst in a chemical reaction?
(1) A catalyst is added as an additional reactant
and is consumed but not regenerated.
(2) A catalyst limits the amount of reactants used.
(3) A catalyst changes the kinds of products produced.
(4) A catalyst provides an alternate reaction pathway that requires less activation energy.
P.S./Chem.–Jan. ’04
greater than the rate of the reverse reaction
less than the rate of the reverse reaction
equal to the rate of the reverse reaction
independent of the rate of the reverse reaction
18 Which statement best explains why most atomic
masses on the Periodic Table are decimal numbers?
(1) Atomic masses are determined relative to an
H–1 standard.
(2) Atomic masses are determined relative to an
O–16 standard.
(3) Atomic masses are a weighted average of the
naturally occurring isotopes.
(4) Atomic masses are an estimated average of
the artificially produced isotopes.
13 Compared to pure water, an aqueous solution of
calcium chloride has a
(1) higher boiling point and higher freezing point
(2) higher boiling point and lower freezing point
(3) lower boiling point and higher freezing point
(4) lower boiling point and lower freezing point
H
2 HBr(g)
22 Which of these elements is the best conductor
of electricity?
(1) S
(3) Br
(2) N
(4) Ni
[3]
[OVER]
23 Given the reaction:
2 Al(s) + Fe2O3(s)
heat
28 Which equation represents a spontaneous nuclear
decay?
(1) C + O2 → CO2
Al2O3(s) + 2 Fe(s)
Which species undergoes reduction?
(1) Al
(2) Fe
(2) H2CO3 → CO2 + H2O
+
Al3
3+
(3)
(4) Fe
(3)
(4)
24 Which energy transformation occurs when an
electrolytic cell is in operation?
(1) chemical energy → electrical energy
(2) electrical energy → chemical energy
(3) light energy → heat energy
(4) light energy → chemical energy
1
+ 42He → 30
15P + 0n
→ –10 e + 90
39 Y
29 The stability of an isotope is based on its
(1) number of neutrons, only
(2) number of protons, only
(3) ratio of neutrons to protons
(4) ratio of electrons to protons
25 Which of these pH numbers indicates the highest level of acidity?
(1) 5
(3) 10
(2) 8
(4) 12
Note that questions 30 and 31 have only three
choices.
30 As the temperature of a substance decreases, the
average kinetic energy of its particles
(1) decreases
(2) increases
(3) remains the same
26 According to the Arrhenius theory, when a base
dissolves in water it produces
–
(1) CO32 as the only negative ion in solution
(2) OH– as the only negative ion in solution
(3) NH4+ as the only positive ion in solution
(4) H+ as the only positive ion in solution
31 When an atom of phosphorus becomes a phos–
phide ion (P 3 ), the radius
(1) decreases
(2) increases
(3) remains the same
27 Which compound is an electrolyte?
(3) CaCl2
(1) C6H12O6
(2) CH3OH
(4) CCl4
P.S./Chem.–Jan. ’04
27 Al
13
90Sr
38
[4]
Part B–1
Answer all questions in this part.
Directions (32–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
32 The data table below represents the properties determined by the analysis of substances A, B, C, and D.
Substance
Melting Point (°C)
Boiling Point (°C)
A
– 80
–20
none
B
20
190
none
C
320
770
as solid
D
800
1250
in solution
Conductivity
Which substance is an ionic compound?
(1) A
(2) B
(3) C
(4) D
33 What is the total number of electrons in a Cr3
ion?
(1) 18
(3) 24
(2) 21
(4) 27
+
36 What is the empirical formula of a compound
with the molecular formula N2O4?
(1) NO
(3) N2O
(2) NO2
(4) N2O3
34 As the atoms of the Group 17 elements in the
ground state are considered from top to bottom,
each successive element has
(1) the same number of valence electrons and
similar chemical properties
(2) the same number of valence electrons and
identical chemical properties
(3) an increasing number of valence electrons
and similar chemical properties
(4) an increasing number of valence electrons
and identical chemical properties
37 What is the correct Lewis electron-dot structure
for the compound magnesium fluoride?
•
•
••
Mg F
••
•
•
•
•
••
(1)
••
Mg+ •• F ••
−
••
(3)
−
••
(2)
35 Which solution when mixed with a drop of
bromthymol blue will cause the indicator to
change from blue to yellow?
(1) 0.1 M HCl
(3) 0.1 M CH3OH
(2) 0.1 M NH3
(4) 0.1 M NaOH
−
+ ••
F •• Mg2 •• F ••
••
•
•
••
••
••
••
••
••
F •• Mg •• F ••
(4)
38 Given the reaction:
Mg(s) + 2 AgNO3(aq) → Mg(NO3)2(aq) + 2 Ag(s)
Which type of reaction is represented?
(1) single replacement (3) synthesis
(2) double replacement (4) decomposition
P.S./Chem.–Jan. ’04
[5]
[OVER]
43 Given the equation:
39 Which equation shows conservation of both
mass and charge?
(1) Cl2 + Br – → Cl – + Br2
+
(2) Cu + 2 Ag + → Cu2 + Ag
+
+
(3) Zn + Cr 3 → Zn2 + Cr
+
+
(4) Ni + Pb2 → Ni2 + Pb
C2H6 + Cl2 → C2H5Cl + HCl
This reaction is best described as
(1) addition involving a saturated hydrocarbon
(2) addition involving an unsaturated hydrocarbon
(3) substitution involving a saturated hydrocarbon
(4) substitution involving an unsaturated hydrocarbon
40 The volume of a gas is 4.00 liters at 293 K and
constant pressure. For the volume of the gas to
become 3.00 liters, the Kelvin temperature
must be equal to
(1)
3.00 × 293
4.00
(3)
3.00 × 4.00
293
(2)
4.00 × 293
3.00
293
(4) 3.00 × 4.00
44 The diagram below shows a key being plated
with copper in an electrolytic cell.
+
41 What is the molarity of a solution containing
20 grams of NaOH in 500 milliliters of solution?
(1) 1 M
(3) 0.04 M
(2) 2 M
(4) 0.5 M
–
A
B
CuSO4(aq)
Copper
electrode
42 Which graph best represents the pressurevolume relationship for an ideal gas at constant
temperature?
Battery
Given the reduction reaction for this cell:
+
Cu2 (aq) + 2e– → Cu(s)
This reduction occurs at
V
P
P
(1)
(3)
V
P.S./Chem.–Jan. ’04
(1)
(2)
(3)
(4)
V
A, which is the anode
A, which is the cathode
B, which is the anode
B, which is the cathode
45 A student neutralized 16.4 milliliters of HCl by
adding 12.7 milliliters of 0.620 M KOH. What
was the molarity of the HCl acid?
(1) 0.168 M
(3) 0.620 M
(2) 0.480 M
(4) 0.801 M
V
P
P
(2)
(4)
46 Nuclear fusion differs from nuclear fission because
nuclear fusion reactions
(1) form heavier isotopes from lighter isotopes
(2) form lighter isotopes from heavier isotopes
(3) convert mass to energy
(4) convert energy to mass
[6]
50 Given the equation:
47 After 32 days, 5 milligrams of an 80-milligram
sample of a radioactive isotope remains
unchanged. What is the half-life of this element?
(1) 8 days
(3) 16 days
(2) 2 days
(4) 4 days
KNO3(s)
H2O()
KNO3(aq)
As H2O() is added toKNO3(s) to form KNO3(aq),
the entropy of the system
48 Which electron configuration represents an
atom of chlorine in an excited state?
(1) 2–8–7
(3) 2–8–6–1
(2) 2–8–8
(4) 2–8–7–1
(1) decreases
(2) increases
(3) remains the same
Note that questions 49 and 50 have only three
choices.
49 As each successive element in Group 15 of the
Periodic Table is considered in order of increasing atomic number, the atomic radius
(1) decreases
(2) increases
(3) remains the same
P.S./Chem.–Jan. ’04
[7]
[OVER]
Part B–2
Answer all questions in this part.
Directions (51–62): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 51 and 52 on the unbalanced equation provided in your answer booklet.
51 Balance the equation in your answer booklet, using the smallest whole-number
coefficients. [1]
52 a Using your balanced equation, show a correct numerical setup for calculating the
total number of moles of H2O(g) produced when 5.0 moles of O2(g) are completely
consumed. Use the space provided in your answer booklet. [1]
b Record your answer. [1]
Base your answers to questions 53 through 55 on the data table provided in your answer booklet.
53 In your answer booklet, record the electronegativity for the elements with atomic
numbers 11 through 17. [1]
54 On the grid provided in your answer booklet, mark an appropriate scale on the axis
labeled “Electronegativity.” [1]
55 On the same grid, plot the data from the data table. Circle and connect the points. [1]
Example:
P.S./Chem.–Jan. ’04
[8]
Base your answers to questions 56 through 58 on the information below.
A student uses 200 grams of water at a temperature of 60°C to prepare a saturated
solution of potassium chloride, KCl.
56 Identify the solute in this solution.
[1]
57 According to Reference Table G, how many grams of KCl must be used to create this
saturated solution? [1]
58 This solution is cooled to 10°C and the excess KCl precipitates (settles out). The resulting solution is saturated at 10°C. How many grams of KCl precipitated out of the
original solution? [1]
Base your answers to questions 59 through 61 on the diagram of the voltaic cell below.
Voltaic Cell
V
Voltmeter
Wire
Switch
Salt
bridge
Pb(s) electrode
2+
Ag(s) electrode
+
Pb (aq)
Ag (aq)
Half-cell 1
Half-cell 2
+
2+
2 Ag (aq) + Pb(s)
Pb (aq) + 2 Ag(s)
59 When the switch is closed, in which half-cell does oxidation occur? [1]
60 When the switch is closed, state the direction that electrons will flow through the wire. [1]
61 Based on the given equation, write the balanced half-reaction that occurs in half-cell 1. [1]
62 In the space provided in your answer booklet, draw a Lewis electron-dot structure for
an atom of phosphorus. [1]
P.S./Chem.–Jan. ’04
[9]
[OVER]
Part C
Answer all questions in this part.
Directions (63–81): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 63 and 64 on the information and the bright-line spectra represented below.
Many advertising signs depend on the production of light emissions from gas-filled
glass tubes that are subjected to a high-voltage source. When light emissions are passed
through a spectroscope, bright-line spectra are produced.
Gas A
Gas B
Gas C
Gas D
Unknown
mixture
63 Identify the two gases in the unknown mixture.
[2]
64 Explain the production of an emission spectrum in terms of the energy states of an
electron. [1]
P.S./Chem.–Jan. ’04
[10]
Base your answers to questions 65 through 67 on the particle diagrams below, which show atoms and/or
molecules in three different samples of matter at STP.
Key
atom of x
atom of y
atom of z
Sample 1
Sample 2
65 Which sample represents a pure substance?
Sample 3
[1]
66 When two atoms of y react with one atom of z, a compound forms. Using the number
of atoms shown in sample 2, what is the maximum number of molecules of this compound that can be formed? [1]
67 Explain why x x does not represent a compound.
[1]
Base your answers to questions 68 through 70 on the information below.
Many artificial flavorings are prepared using the type of organic reaction shown below.
H O
H C C
H H H
OH
H
Reactant 1
H O
+ HO C C C H
H H H
H C C O C C C H +
H H H
H
HOH
H H H
Reactant 2
68 What is the name of this organic reaction?
[1]
69 To what class of organic compounds does reactant 2 belong?
[1]
70 In the space provided in your answer booklet, draw the structural formula of an isomer
of reactant 2. [1]
P.S./Chem.–Jan. ’04
[11]
[OVER]
Base your answers to questions 71 through 74 on the article below, the Reference Tables for Physical
Setting/Chemistry, and your knowledge of chemistry.
Radioactivity at home
You may be surprised to learn that you do not need to visit a nuclear power plant or a
hospital X-ray laboratory to find sources of radioactivity. They are all around us. In fact, it
is likely that you’ll find a few at home. Your front porch may incorporate cinder blocks or
granite blocks. Both contain uranium. Walk through the front door, look up, and you’ll see
a smoke detector that owes its effectiveness to the constant source of alpha particle emissions from Americium-241. As long as the gases remain ionized within the shielded container, electricity flows, and all is calm. When smoke enters the chamber, it neutralizes the
charges on these ions. In the absence of these ions, the circuit breaks and the alarm goes
off.
Indicator lights on your appliances may use Krypton-85; electric blankets, promethium147; and fluorescent lights, thorium-229. Even the food we eat is radioactive. The more
potassium-rich the food source, the more potassium-40—a radioactive isotope that makes
up about 0.01% of the natural supply of this mineral—is present. Thus, brazil nuts, peanuts,
bananas, potatoes, and flour, all rich in potassium, are radiation sources.
—Chem Matters
April 2000
71 Write the equation for the alpha decay that occurs in a smoke detector containing
Americium-241 (Am-241). [2]
72 How is the radioactive decay of Krypton-85 different from the radioactive decay of
Americium-241? [1]
73 State one benefit or useful application of radioactivity not mentioned in this article. [1]
74 State one risk or danger associated with radioactivity.
[1]
Base your answers to questions 75 and 76 on the information below.
Gypsum is a mineral that is used in the construction industry to make drywall (sheetrock).
The chemical formula for this hydrated compound is CaSO4 • 2 H2O. A hydrated compound
contains water molecules within its crystalline structure. Gypsum contains 2 moles of water
for each 1 mole of calcium sulfate.
75 What is the gram formula mass of CaSO4 • 2 H2O?
[1]
76 a In the space provided in your answer booklet, show a correct numerical setup for calculating the percent composition by mass of water in this compound. [1]
b Record your answer. [1]
P.S./Chem.–Jan. ’04
[12]
Base your answers to questions 77 through 79 on the information and potential energy diagram below.
Potential Energy
Chemical cold packs are often used to reduce swelling after an athletic injury. The diagram represents the potential energy changes when a cold pack is activated.
C
A
B
D
Reaction Coordinate
77 Which lettered interval on the diagram represents the potential energy of the products? [1]
78 Which lettered interval on the diagram represents the heat of reaction? [1]
79 Identify a reactant listed in Reference Table I that could be mixed with water for use in
a chemical cold pack. [1]
Base your answers to questions 80 and 81 on the information below.
Calcium hydroxide is commonly known as agricultural lime and is used to adjust the soil
pH. Before the lime was added to a field, the soil pH was 5. After the lime was added, the
soil underwent a 100-fold decrease in hydronium ion concentration.
80 What is the new pH of the soil in the field? [1]
81 According to Reference Table F, calcium hydroxide is soluble in water. Identify another
hydroxide compound that contains a Group 2 element and is also soluble in water. [1]
P.S./Chem.–Jan. ’04
[13]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Wednesday, January 28, 2004 — 9:15 a.m. to 12:15 p.m., only
Student
ANSWER SHEET
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sex:
Teacher
..............................................
■ Male ■ Female Grade
...........
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
12 . . . . . . . . . . . .
23 . . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
2 ............
13 . . . . . . . . . . . .
24 . . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
3 ............
14 . . . . . . . . . . . .
25 . . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
4 ............
15 . . . . . . . . . . . .
26 . . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
5 ............
16 . . . . . . . . . . . .
27 . . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
6 ............
17 . . . . . . . . . . . .
28 . . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
7 ............
18 . . . . . . . . . . . .
29 . . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
8 ............
19 . . . . . . . . . . . .
30 . . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
9 ............
20 . . . . . . . . . . . .
31 . . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part A Score
10 . . . . . . . . . . . .
21 . . . . . . . . . . . .
11 . . . . . . . . . . . .
22 . . . . . . . . . . . .
Part B–1 Score
41 . . . . . . . . . . . .
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Wednesday, June 23, 2004 — 9:15 a.m. to 12:15 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for your use while taking this examination.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–33): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
7 Given the reaction:
N2(g) + 3 H2(g)
1 The modern model of the atom is based on the
work of
(1) one scientist over a short period of time
(2) one scientist over a long period of time
(3) many scientists over a short period of time
(4) many scientists over a long period of time
What is the mole-to-mole ratio between nitrogen gas and hydrogen gas?
(1) 1:2
(2) 1:3
2 Which statement is true about the charges
assigned to an electron and a proton?
(1) Both an electron and a proton are positive.
(2) An electron is positive and a proton is negative.
(3) An electron is negative and a proton is positive.
(4) Both an electron and a proton are negative.
(3) 2:2
(4) 2:3
8 What is the percent by mass of oxygen in
propanal, CH3CH2CHO?
(1) 10.0%
(3) 38.1%
(2) 27.6%
(4) 62.1%
9 Covalent bonds are formed when electrons are
(1) transferred from one atom to another
(2) captured by the nucleus
(3) mobile within a metal
(4) shared between two atoms
3 In the wave-mechanical model, an orbital is a
region of space in an atom where there is
(1) a high probability of finding an electron
(2) a high probability of finding a neutron
(3) a circular path in which electrons are found
(4) a circular path in which neutrons are found
10 Which type of molecule is CF4?
(1) polar, with a symmetrical distribution of
charge
(2) polar, with an asymmetrical distribution of
charge
(3) nonpolar, with a symmetrical distribution of
charge
(4) nonpolar, with an asymmetrical distribution
of charge
4 What is the charge of the nucleus in an atom of
oxygen-17?
(1) 0
(3) +8
(2) –2
(4) +17
5 Which pair of symbols represents a metalloid
and a noble gas?
(1) Si and Bi
(3) Ge and Te
(2) As and Ar
(4) Ne and Xe
11 Which change occurs when a barium atom loses
two electrons?
(1) It becomes a negative ion and its radius
decreases.
(2) It becomes a negative ion and its radius
increases.
(3) It becomes a positive ion and its radius
decreases.
(4) It becomes a positive ion and its radius
increases.
6 Which statement describes a chemical property
of iron?
(1) Iron can be flattened into sheets.
(2) Iron conducts electricity and heat.
(3) Iron combines with oxygen to form rust.
(4) Iron can be drawn into a wire.
P.S./Chem.–June ’04
2 NH3(g)
[2]
18 Which sample contains particles in a rigid, fixed,
geometric pattern?
(1) CO2(aq)
(3) H2O()
(2) HCl(g)
(4) KCl(s)
12 Conductivity in a metal results from the metal
atoms having
(1) high electronegativity
(2) high ionization energy
(3) highly mobile protons in the nucleus
(4) highly mobile electrons in the valence shell
19 Given the reaction at 25°C:
Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g)
13 Which of these elements has the least attraction
for electrons in a chemical bond?
(1) oxygen
(3) nitrogen
(2) fluorine
(4) chlorine
The rate of this reaction can be increased by
using 5.0 grams of powdered zinc instead of a
5.0-gram strip of zinc because the powdered
zinc has
(1)
(2)
(3)
(4)
14 Recovering the salt from a mixture of salt and
water could best be accomplished by
(1) evaporation
(2) filtration
(3) paper chromatography
(4) density determination
20 Which statement about a system at equilibrium
is true?
(1) The forward reaction rate is less than the
reverse reaction rate.
(2) The forward reaction rate is greater than the
reverse reaction rate.
(3) The forward reaction rate is equal to the
reverse reaction rate.
(4) The forward reaction rate stops and the
reverse reaction rate continues.
15 The average kinetic energy of water molecules is
greatest in which of these samples?
(1) 10 g of water at 35°C
(2) 10 g of water at 55°C
(3) 100 g of water at 25°C
(4) 100 g of water at 45°C
16 Helium is most likely to behave as an ideal gas
when it is under
(1) high pressure and high temperature
(2) high pressure and low temperature
(3) low pressure and high temperature
(4) low pressure and low temperature
21 A catalyst increases the rate of a chemical reaction by
(1) lowering the activation energy of the reaction
(2) lowering the potential energy of the products
(3) raising the temperature of the reactants
(4) raising the concentration of the reactants
17 At STP, the element oxygen can exist as either
O2 or O3 gas molecules. These two forms of the
element have
(1) the same chemical and physical properties
(2) the same chemical properties and different
physical properties
(3) different chemical properties and the same
physical properties
(4) different chemical and physical properties
P.S./Chem.–June ’04
lower kinetic energy
lower concentration
more surface area
more zinc atoms
22 Which element must be present in an organic
compound?
(1) hydrogen
(3) carbon
(2) oxygen
(4) nitrogen
23 Which compound is a saturated hydrocarbon?
(1) hexane
(3) hexanol
(2) hexene
(4) hexanal
[3]
[OVER]
24 Given the reaction:
O
O
CH3C—O—C2H5 + H2O
CH3C— OH + HOC2H5
This reaction is an example of
(1) fermentation
(2) saponification
(3) hydrogenation
(4) esterification
25 Which of these compounds has chemical properties most similar to the chemical properties of
ethanoic acid?
(1) C3H7COOH
(3) C2H5COOC2H5
(2) C2H5OH
(4) C2H5OC2H5
30 Which compound could serve as a reactant in a
neutralization reaction?
(1) NaCl
(3) CH3OH
(2) KOH
(4) CH3CHO
31 Which of these particles has the greatest mass?
(1) alpha
(3) neutron
(2) beta
(4) positron
26 Given the reaction that occurs in an electrochemical cell:
Zn(s) + CuSO4(aq) → ZnSO4(aq) + Cu(s)
During this reaction, the oxidation number of
Zn changes from
(1) 0 to +2
(2) 0 to –2
32 In a nuclear fusion reaction, the mass of the
products is
(1) less than the mass of the reactants because
some of the mass has been converted to
energy
(2) less than the mass of the reactants because
some of the energy has been converted to
mass
(3) more than the mass of the reactants because
some of the mass has been converted to
energy
(4) more than the mass of the reactants because
some of the energy has been converted to
mass
(3) +2 to 0
(4) –2 to 0
27 A voltaic cell spontaneously converts
(1) electrical energy to chemical energy
(2) chemical energy to electrical energy
(3) electrical energy to nuclear energy
(4) nuclear energy to electrical energy
28 Which pair of formulas represents two compounds that are electrolytes?
(1) HCl and CH3OH
(2) HCl and NaOH
(3) C5H12 and CH3OH
(4) C5H12 and NaOH
33 Which of these types of radiation has the greatest penetrating power?
(1) alpha
(3) gamma
(2) beta
(4) positron
29 Hydrogen chloride, HCl, is classified as an
Arrhenius acid because it produces
(1) H+ ions in aqueous solution
(2) Cl– ions in aqueous solution
(3) OH– ions in aqueous solution
(4) NH4+ ions in aqueous solution
P.S./Chem.–June ’04
[4]
Part B–1
Answer all questions in this part.
Directions (34–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
40 The graph below represents the uniform heating of a substance, starting with the substance as
a solid below its melting point.
Temperature
34 How many electrons are contained in an Au3+ ion?
(1) 76
(3) 82
(2) 79
(4) 197
35 Which electron configuration represents the
electrons of an atom in an excited state?
(1) 2–4
(3) 2–7–2
(2) 2–6
(4) 2–8–2
36 In comparison to an atom of 199 F in the ground
state, an atom of 126 C in the ground state has
(1) three fewer neutrons
(2) three fewer valence electrons
(3) three more neutrons
(4) three more valence electrons
E
D
B
C
A
Time
Which line segment represents an increase in
potential energy and no change in average
kinetic energy?
(1) AB
(2) BC
37 Element X is a solid that is brittle, lacks luster,
and has six valence electrons. In which group on
the Periodic Table would element X be found?
(1) 1
(3) 15
(2) 2
(4) 16
(3) CD
(4) EF
41 Using your knowledge of chemistry and the information in Reference Table H, which statement
concerning propanone and water at 50°C is true?
(1) Propanone has a higher vapor pressure and
stronger intermolecular forces than water.
(2) Propanone has a higher vapor pressure and
weaker intermolecular forces than water.
(3) Propanone has a lower vapor pressure and
stronger intermolecular forces than water.
(4) Propanone has a lower vapor pressure and
weaker intermolecular forces than water.
38 What is the empirical formula for the compound C6H12O6?
(3) C3H6O3
(1) CH2O
(2) C2H4O2
(4) C6H12O6
39 The bonds between hydrogen and oxygen in a
water molecule are classified as
(1) polar covalent
(2) nonpolar covalent
(3) ionic
(4) metallic
P.S./Chem.–June ’04
F
42 A solution that is at equilibrium must be
(1) concentrated
(3) saturated
(2) dilute
(4) unsaturated
[5]
[OVER]
43 Given the reaction:
N2(g) + O2(g) + 182.6 kJ
47 Which structural formula represents an ether?
2 NO(g)
Which change would cause an immediate
increase in the rate of the forward reaction?
(1)
(2)
(3)
(4)
H
H
H
H
C
C
C
C
H
H
H
C
H
H
H
H
C
C
H
H
(1)
(1)
(2)
(3)
(4)
H
H H
C
C H
C
H
H
H
H
H
(2)
P.S./Chem.–June ’04
C
H
H
H
O
C
C
OH
(3)
H
OH
H
C
H
O
H
C
H
H
(4)
C
C
Al + 3e– → Al3+
Al → Al3+ + 3e–
O2 + 4e– → 2 O2–
O2 → 2 O2– + 4e–
49 Based on Reference Table N, what fraction of a
sample of gold-198 remains radioactive after
2.69 days?
(1) 14
(3) 34
C H
H H
(2)
H
H C
C
Which half-reaction correctly represents the
oxidation that occurs?
(3)
C
H
48 Given the reaction for the corrosion of aluminum:
4 Al + 3 O2 → 2 Al2O3
H
H
H
H
H
H
(2)
46 Which structural formula represents 2-pentyne?
H
C
H
45 Which pH indicates a basic solution?
(1) 1
(3) 7
(2) 5
(4) 12
H
C
H
(1)
H2O(g) at 120°C
H2O() at 80°C
H2O() at 20°C
H2O(s) at 0°C
H
O
H
increasing the concentration of NO(g)
increasing the concentration of N2(g)
decreasing the reaction temperature
decreasing the reaction pressure
44 Which 10-milliliter sample of water has the
greatest degree of disorder?
(1)
(2)
(3)
(4)
H
1
2
(4)
7
8
Note that question 50 has only three choices.
H
H
H
H
C
C
C
H
H
H
C
C
H
H
50 As the elements of Group 1 on the Periodic
Table are considered in order of increasing
atomic radius, the ionization energy of each successive element generally
(1) decreases
(2) increases
(3) remains the same
H
(4)
[6]
Part B–2
Answer all questions in this part.
Directions (51–64): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 51 through 53 on the balanced chemical equation below.
2 H2O → 2 H2 + O2
51 What type of reaction does this equation represent?
[1]
52 How does the balanced chemical equation show the Law of Conservation of Mass? [1]
53 What is the total number of moles of O2 produced when 8 moles of H2O is completely
consumed? [1]
Base your answers to questions 54 and 55 on the unbalanced redox reaction below.
Cu(s) + AgNO3(aq) → Cu(NO3)2(aq) + Ag(s)
54 Write the reduction half-reaction.
[1]
55 Balance the redox equation in your answer booklet, using the smallest whole-number
coefficients. [1]
Base your answers to questions 56 through 58 on the information below.
A student titrates 60.0 mL of HNO3(aq) with 0.30 M NaOH(aq). Phenolphthalein
is used as the indicator. After adding 42.2 mL of NaOH(aq), a color change remains
for 25 seconds, and the student stops the titration.
56 What color change does phenolphthalein undergo during this titration?
[1]
57 In the space provided in your answer booklet, show a correct numerical setup for
calculating the molarity of the HNO3(aq). [1]
58 According to the data, how many significant figures should be present in the calculated
molarity of the HNO3(aq)? [1]
P.S./Chem.–June ’04
[7]
[OVER]
Base your answers to questions 59 through 61 on the data table below, which shows three isotopes of neon.
Isotope
Atomic Mass
Percent Natural
(atomic mass units)
Abundance
20Ne
19.99
90.9%
21Ne
20.99
0.3%
22Ne
21.99
8.8%
59 In terms of atomic particles, state one difference between these three isotopes of neon. [1]
60 Based on the atomic masses and the natural abundances shown in the data table, in the
space provided in your answer booklet, show a correct numerical setup for calculating
the average atomic mass of neon. [1]
61 Based on natural abundances, the average atomic mass of neon is closest to which
whole number? [1]
62 Based on the Periodic Table, explain why Na and K have similar chemical properties. [1]
63 In the space to the right of the reactants and arrow provided in your answer booklet,
draw the structural formula for the product of the reaction shown. [1]
64 Given the nuclear equation:
58 Cu
29
→ 58
28 Ni + X
What nuclear particle is represented by X?
P.S./Chem.–June ’04
[8]
[1]
Part C
Answer all questions in this part.
Directions (65–85): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 65 through 67 on the information and equation below.
Antacids can be used to neutralize excess stomach acid. Brand A antacid contains the acidneutralizing agent magnesium hydroxide, Mg(OH)2. It reacts with HCl(aq) in the stomach,
according to the following balanced equation:
2 HCl(aq) + Mg(OH)2(s) → MgCl2(aq) + 2 H2O()
65 In the space provided in your answer booklet, show a correct numerical setup for calculating the number of moles of Mg(OH)2 (gram-formula mass = 58.3 grams/mole) in
an 8.40-gram sample. [1]
66 If a person produces 0.050 mole of excess HCl in the stomach, how many moles of
Mg(OH)2 are needed to neutralize this excess hydrochloric acid? [1]
67 Brand B antacid contains the acid-neutralizing agent sodium hydrogen carbonate. Write
the chemical formula for sodium hydrogen carbonate. [1]
Base your answers to questions 68 through 70 on the information below.
Naphthalene, a nonpolar substance that sublimes at room temperature, can be used to
protect wool clothing from being eaten by moths.
68 Explain, in terms of intermolecular forces, why naphthalene sublimes.
69 Explain why naphthalene is not expected to dissolve in water.
[1]
[1]
70 The empirical formula for naphthalene is C5H4 and the molecular mass of naphthalene is
128 grams/mole. What is the molecular formula for naphthalene? [1]
P.S./Chem.–June ’04
[9]
[OVER]
Base your answers to questions 71 through 74 on the data table below, which shows the solubility of a solid
solute.
The Solubility of the Solute at
Various Temperatures
Solute per
Temperature
100 g of H2O(g)
(°C)
0
18
20
20
40
24
60
29
80
36
100
49
71 On the grid provided in your answer booklet, mark an appropriate scale on the axis
labeled “Solute per 100 g of H2O(g).” An appropriate scale is one that allows a trend to
be seen. [1]
72 On the same grid, plot the data from the data table. Circle and connect the points. [1]
Example:
73 Based on the data table, if 15 grams of solute is dissolved in 100 grams of water at 40°C,
how many more grams of solute can be dissolved in this solution to make it saturated at
40°C? [1]
74 According to Reference Table G, how many grams of KClO3 must be dissolved in
100 grams of H2O at 10°C to produce a saturated solution? [1]
Base your answers to questions 75 through 78 on the information below.
A weather balloon has a volume of 52.5 liters at a temperature of 295 K. The balloon is
released and rises to an altitude where the temperature is 252 K.
75 How does this temperature change affect the gas particle motion?
[1]
76 The original pressure at 295 K was 100.8 kPa and the pressure at the higher altitude at
252 K is 45.6 kPa. Assume the balloon does not burst. In the space provided in your
answer booklet, show a correct numerical setup for calculating the volume of the balloon at the higher altitude. [1]
77 What Celsius temperature is equal to 252 K?
[1]
78 What pressure, in atmospheres (atm), is equal to 45.6 kPa? [1]
P.S./Chem.–June ’04
[10]
Base your answers to questions 79 and 80 on the information and equation below.
Human blood contains dissolved carbonic acid, H2CO3, in equilibrium with carbon
dioxide and water. The equilibrium system is shown below.
H2CO3(aq)
CO2(aq) + H2O()
79 Explain, using LeChatelier’s principle, why decreasing the concentration of CO2
decreases the concentration of H2CO3. [1]
80 What is the oxidation number of carbon in H2CO3(aq)?
[1]
Base your answers to questions 81 through 84 on the information below.
A safe level of fluoride ions is added to many public drinking water supplies. Fluoride
ions have been found to help prevent tooth decay. Another common source of fluoride ions
is toothpaste. One of the fluoride compounds used in toothpaste is tin(II) fluoride.
A town located downstream from a chemical plant was concerned about fluoride ions
from the plant leaking into its drinking water. According to the Environmental Protection
Agency, the fluoride ion concentration in drinking water cannot exceed 4 ppm. The town
hired a chemist to analyze its water. The chemist determined that a 175-gram sample of the
town’s water contains 0.000 250 gram of fluoride ions.
81 In the box provided in your answer booklet, draw a Lewis electron-dot diagram for a
fluoride ion. [1]
82 What is the chemical formula for tin(II) fluoride?
[1]
83 How many parts per million of fluoride ions are present in the analyzed sample?
[1]
84 Is the town’s drinking water safe to drink? Support your decision using information in
the passage and your calculated fluoride level in question 83. [1]
85 A plan is being developed for an experiment to test the effect of concentrated strong
acids on a metal surface protected by various coatings. Some safety precautions would
be the wearing of chemical safety goggles, an apron, and gloves. State one additional
safety precaution that should be included in the plan. [1]
P.S./Chem.–June ’04
[11]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Wednesday, June 23, 2004 — 9:15 a.m. to 12:15 p.m., only
ANSWER SHEET
■ Male ■ Female Grade
Student
..............................................
Sex:
...........
Teacher
..............................................
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
12 . . . . . . . . . . . .
23 . . . . . . . . . . .
34 . . . . . . . . . . . .
43 . . . . . . . . . . . .
2 ............
13 . . . . . . . . . . . .
24 . . . . . . . . . . .
35 . . . . . . . . . . . .
44 . . . . . . . . . . . .
3 ............
14 . . . . . . . . . . . .
25 . . . . . . . . . . .
36 . . . . . . . . . . . .
45 . . . . . . . . . . . .
4 ............
15 . . . . . . . . . . . .
26 . . . . . . . . . . .
37 . . . . . . . . . . . .
46 . . . . . . . . . . . .
5 ............
16 . . . . . . . . . . . .
27 . . . . . . . . . . .
38 . . . . . . . . . . . .
47 . . . . . . . . . . . .
6 ............
17 . . . . . . . . . . . .
28 . . . . . . . . . . .
39 . . . . . . . . . . . .
48 . . . . . . . . . . . .
7 ............
18 . . . . . . . . . . . .
29 . . . . . . . . . . .
40 . . . . . . . . . . . .
49 . . . . . . . . . . . .
8 ............
19 . . . . . . . . . . . .
30 . . . . . . . . . . .
41 . . . . . . . . . . . .
50 . . . . . . . . . . . .
9 ............
20 . . . . . . . . . . . .
31 . . . . . . . . . . .
42 . . . . . . . . . . . .
10 . . . . . . . . . . . .
21 . . . . . . . . . . . .
32 . . . . . . . . . . .
11 . . . . . . . . . . . .
22 . . . . . . . . . . . .
33 . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Tuesday, August 17, 2004 — 12:30 to 3:30 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–33): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
1 Which of these phrases best describes an atom?
(1) a positive nucleus surrounded by a hard
negative shell
(2) a positive nucleus surrounded by a cloud of
negative charges
(3) a hard sphere with positive particles uniformly embedded
(4) a hard sphere with negative particles uniformly embedded
6 At 298 K, oxygen (O2) and ozone (O3) have
different properties because their
(1) atoms have different atomic numbers
(2) atoms have different atomic masses
(3) molecules have different molecular structures
(4) molecules have different average kinetic
energies
7 Which substance represents a compound?
(1) C(s)
(3) CO(g)
(2) Co(s)
(4) O2(g)
2 Which statement is true about a proton and an
electron?
(1) They have the same masses and the same
charges.
(2) They have the same masses and different
charges.
(3) They have different masses and the same
charges.
(4) They have different masses and different
charges.
8 All chemical reactions have a conservation of
(1) mass, only
(2) mass and charge, only
(3) charge and energy, only
(4) mass, charge, and energy
9 Which characteristic is a property of molecular
substances?
(1) good heat conductivity
(2) good electrical conductivity
(3) low melting point
(4) high melting point
3 The atomic mass of an element is the weighted
average of the masses of
(1) its two most abundant isotopes
(2) its two least abundant isotopes
(3) all of its naturally occurring isotopes
(4) all of its radioactive isotopes
10 Given the Lewis electron-dot diagram:
H
4 What determines the order of placement of the
elements on the modern Periodic Table?
(1) atomic number
(2) atomic mass
(3) the number of neutrons, only
(4) the number of neutrons and protons
H C H
H
Which electrons are represented by all of the dots?
(1)
(2)
(3)
(4)
5 Which compound contains only covalent bonds?
(1) NaOH
(3) Ca(OH)2
(2) Ba(OH)2
(4) CH3OH
P.S./Chem.–Aug. ’04
[2]
the carbon valence electrons, only
the hydrogen valence electrons, only
the carbon and hydrogen valence electrons
all of the carbon and hydrogen electrons
11 Which grouping of the three phases of bromine is
listed in order from left to right for increasing distance between bromine molecules?
(1) gas, liquid, solid
(3) solid, gas, liquid
(2) liquid, solid, gas
(4) solid, liquid, gas
17 Which process represents a chemical change?
(1) melting of ice
(2) corrosion of copper
(3) evaporation of water
(4) crystallization of sugar
12 Which statement concerning elements is true?
(1) Different elements must have different numbers of isotopes.
(2) Different elements must have different numbers of neutrons.
(3) All atoms of a given element must have the
same mass number.
(4) All atoms of a given element must have the
same atomic number.
18 At STP, which 4.0-gram zinc sample will react
fastest with dilute hydrochloric acid?
(1) lump
(3) powdered
(2) bar
(4) sheet metal
13 At room temperature,
solute in water would
change in pressure?
(1) methanol
(2) sugar
19 Which information about a chemical reaction is
provided by a potential energy diagram?
(1) the oxidation states of the reactants and
products
(2) the average kinetic energy of the reactants
and products
(3) the change in solubility of the reacting
substances
(4) the energy released or absorbed during the
reaction
the solubility of which
be most affected by a
(3) carbon dioxide
(4) sodium nitrate
20 A catalyst works by
(1) increasing the potential energy of the reactants
(2) increasing the energy released during a reaction
(3) decreasing the potential energy of the products
(4) decreasing the activation energy required for
a reaction
14 Based on Reference Table I, which change
occurs when pellets of solid NaOH are added to
water and stirred?
(1) The water temperature increases as chemical
energy is converted to heat energy.
(2) The water temperature increases as heat
energy is stored as chemical energy.
(3) The water temperature decreases as chemical energy is converted to heat energy.
(4) The water temperature decreases as heat
energy is stored as chemical energy.
21 Even though the process is endothermic, snow
can sublime. Which tendency in nature accounts
for this phase change?
(1) a tendency toward greater entropy
(2) a tendency toward greater energy
(3) a tendency toward less entropy
(4) a tendency toward less energy
15 The concept of an ideal gas is used to explain
(1) the mass of a gas sample
(2) the behavior of a gas sample
(3) why some gases are monatomic
(4) why some gases are diatomic
22 What is the IUPAC name of the compound with
the structural formula shown below?
16 Molecules in a sample of NH3() are held closely
together by intermolecular forces
(1) existing between ions
(2) existing between electrons
(3) caused by different numbers of neutrons
(4) caused by unequal charge distribution
P.S./Chem.–Aug. ’04
H
H
H
H
C
C
C
H
H
(1) 2-pentene
(2) 3-pentene
[3]
H
C
C
H
H
H
(3) 2-pentyne
(4) 3-pentyne
[OVER]
23 Molecules of 1-bromopropane and 2-bromopropane differ in
(1) molecular formula
(2) structural formula
(3) number of carbon atoms per molecule
(4) number of bromine atoms per molecule
28 The only positive ion found in an aqueous solution of sulfuric acid is the
(1) hydroxide ion
(3) sulfite ion
(2) hydronium ion
(4) sulfate ion
29 Which process uses a volume of solution of
known concentration to determine the concentration of another solution?
(1) distillation
(3) transmutation
(2) substitution
(4) titration
24 Which half-reaction correctly represents reduction?
3+
–
(1) Ag → Ag+ + e–
(3) Au + 3e → Au
2+
–
3+
(2) F2 → 2 F – + 2e–
(4) Fe + e → Fe
30 Which pH change represents a hundredfold
increase in the concentration of H3O+?
(1) pH 5 to pH 7
(3) pH 3 to pH 1
(2) pH 13 to pH 14
(4) pH 4 to pH 3
25 In a redox reaction, how does the total number of
electrons lost by the oxidized substance compare
to the total number of electrons gained by the
reduced substance?
(1) The number lost is always greater than the
number gained.
(2) The number lost is always equal to the number
gained.
(3) The number lost is sometimes equal to the
number gained.
(4) The number lost is sometimes less than the
number gained.
31 Which radioisotope undergoes beta decay and
has a half-life of less than 1 minute?
(1) Fr-220
(3) N-16
(2) K-42
(4) P-32
32 Which set of symbols represents atoms with
valence electrons in the same electron shell?
(1) Ba, Br, Bi
(3) O, S, Te
(2) Sr, Sn, I
(4) Mn, Hg, Cu
26 Which reaction is an example of an oxidationreduction reaction?
(1) AgNO3 + KI → AgI + KNO3
(2) Cu + 2 AgNO3 → Cu(NO3)2 + 2 Ag
(3) 2 KOH + H2SO4 → K2SO4 + 2 H2O
(4) Ba(OH)2 + 2 HCl → BaCl2 + 2 H2O
Note that question 33 has only three choices.
33 When compared with the energy of an electron in
the first shell of a carbon atom, the energy of an
electron in the second shell of a carbon atom is
(1) less
(2) greater
(3) the same
27 Which compound is an Arrhenius base?
(3) LiOH
(1) CH3OH
(2) CO2
(4) NO2
P.S./Chem.–Aug. ’04
[4]
Part B–1
Answer all questions in this part.
Directions (34–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
34 What is the total number of electrons found in an
atom of sulfur?
(1) 6
(3) 16
(2) 8
(4) 32
40 At STP, which of these substances is most soluble
in H2O?
(3) HCl
(1) CCl4
(2) CO2
(4) N2
35 Which electron configuration represents the
electrons of an atom in an excited state?
(1) 2–8–1
(3) 2–8–17–6
(2) 2–8–6
(4) 2–8–18–5
41 Based on intermolecular forces, which of these
substances would have the highest boiling point?
(1) He
(3) CH4
(2) O2
(4) NH3
36 The nucleus of an atom of cobalt-58 contains
(1) 27 protons and 31 neutrons
(2) 27 protons and 32 neutrons
(3) 59 protons and 60 neutrons
(4) 60 protons and 60 neutrons
42 How much heat energy must be absorbed to
completely melt 35.0 grams of H2O(s) at 0°C?
(1) 9.54 J
(3) 11 700 J
(2) 146 J
(4) 79 100 J
43 The graph below represents the uniform heating
of a substance, starting below its melting point,
when the substance is solid.
38 Which substance is correctly paired with its type
of bonding?
(1) NaBr—nonpolar covalent
(2) HCl—nonpolar covalent
(3) NH3—polar covalent
(4) Br2—polar covalent
D
B
E
C
A
Time
Which line segments represent an increase in
average kinetic energy?
39 A gas occupies a volume of 444 mL at 273 K and
79.0 kPa. What is the final kelvin temperature
when the volume of the gas is changed to 1880 mL
and the pressure is changed to 38.7 kPa?
(1) 31.5 K
(3) 566 K
(2) 292 K
(4) 2360 K
P.S./Chem.–Aug. ’04
F
Temperature
37 Which pair of formulas correctly represents a
molecular formula and its corresponding empirical formula?
(1) C2H2 and CH
(3) C4H6 and CH
(2) C3H4 and CH2
(4) C5H8 and C2H2
(1) AB and BC
(2) AB and CD
[5]
(3) BC and DE
(4) DE and EF
[OVER]
44 Given the three organic structural formulas shown below:
H
H
O
H
C
C
C
H
H
H
H
H
O
C
C
H
OH
H
H
OH H
C
C
C
H
H
H
H
Which organic-compound classes are represented by these structural formulas, as
shown from left to right?
(1) ester, organic acid, ketone
(3) ketone, aldehyde, alcohol
(2) ester, aldehyde, organic acid
(4) ketone, organic acid, alcohol
48 Which statement correctly describes a solution
with a pH of 9?
45 Given the reaction at equilibrium:
2 NO(g)
N2(g) + O2(g) + energy
(1) It has a higher concentration of H3O+ than
OH– and causes litmus to turn blue.
(2) It has a higher concentration of OH– than
H3O+ and causes litmus to turn blue.
(3) It has a higher concentration of H3O+ than
OH– and causes methyl orange to turn yellow.
(4) It has a higher concentration of OH– than
H3O+ and causes methyl orange to turn red.
Which change will result in a decrease in the
amount of NO(g) formed?
(1)
(2)
(3)
(4)
decreasing the pressure
decreasing the concentration of N2(g)
increasing the concentration of O2(g)
increasing the temperature
46 Given the equation:
X + Cl2 → C2H5Cl + HCl
49 How many days are required for 200. grams of
radon-222 to decay to 50.0 grams?
(1) 1.91 days
(3) 7.64 days
(2) 3.82 days
(4) 11.5 days
Which molecule is represented by X?
(1) C2H4
(2) C2H6
(3) C3H6
(4) C3H8
47 Which metal reacts spontaneously with a solution
containing zinc ions?
(1) magnesium
(3) copper
(2) nickel
(4) silver
P.S./Chem.–Aug. ’04
50 A student calculates the density of an unknown
solid. The mass is 10.04 grams, and the volume is
8.21 cubic centimeters. How many significant figures should appear in the final answer?
(1) 1
(3) 3
(2) 2
(4) 4
[6]
Part B–2
Answer all questions in this part.
Directions (51–65): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
51 In the 19th century, Dmitri Mendeleev predicted the existence of a then unknown
element X with a mass of 68. He also predicted that an oxide of X would have the
formula X2O3. On the modern Periodic Table, what is the group number and period
number of element X? [1]
52 Given the equation:
2 H2(g) + O2(g) → 2 H2O(g)
If 8.0 moles of O2 are completely consumed, what is the total number of moles of H2O
produced? [1]
53 In the space provided in your answer booklet, show a correct numerical setup for determining how many liters of a 1.2 M solution can be prepared with 0.50 mole of C6H12O6.
[1]
Base your answers to questions 54 through 57 on the particle diagrams below. Samples A, B, and C contain
molecules at STP.
A
B
C
54 Explain why the average kinetic energy of sample B is equal to the average kinetic
energy of sample C. [1]
55 Explain, in terms of the composition, why sample A represents a pure substance.
[1]
56 Explain why sample C could represent a mixture of fluorine and hydrogen chloride. [1]
57 Contrast sample A and sample B, in terms of compounds and mixtures. Include both
sample A and sample B in your answer. [1]
P.S./Chem.–Aug. ’04
[7]
[OVER]
Base your answers to questions 58 through 60 on the electronegativity values and atomic numbers of
fluorine, chlorine, bromine, and iodine that are listed on Reference Table S.
58 On the grid provided in your answer booklet, mark an appropriate scale on the axis
labeled “Electronegativity.” An appropriate scale is one that allows a trend to be seen. [1]
59 On the same grid, plot the electronegativity and atomic number data from Reference
Table S. Circle and connect the points. [1]
Example:
60 Explain, in terms of electronegativity, why the H–F bond is expected to be more polar
than the H–I bond. [1]
61 What is the gram-formula mass of (NH4)2CO3? Use atomic masses rounded to the
nearest whole number. [1]
62 In the space provided in your answer booklet, show a correct numerical setup for
calculating the number of moles of CO2 (gram-formula mass = 44 g/mol) present in
11 grams of CO2. [1]
Base your answers to questions 63 and 64 on the information below.
Given the equilibrium equation at 298 K:
KNO3(s) + 34.89 kJ
H2O
–
K+(aq) + NO3 (aq)
63 Describe, in terms of LeChatelier’s principle, why an increase in temperature increases
the solubility of KNO3. [1]
64 The equation indicates that KNO3 has formed a saturated solution. Explain, in terms of
equilibrium, why the solution is saturated. [1]
65 In the space provided in your answer booklet, draw the structural formula for butanoic
acid. [1]
P.S./Chem.–Aug. ’04
[8]
Part C
Answer all questions in this part.
Directions (66–85): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 66 through 69 on the information below, which describes the smelting of
iron ore, and on your knowledge of chemistry.
In the smelting of iron ore, Fe2O3 is reduced in a blast furnace at high temperature by
a reaction with carbon monoxide. Crushed limestone, CaCO3, is also added to the mixture
to remove impurities in the ore. The carbon monoxide is formed by the oxidation of carbon
(coke), as shown in the reaction below:
2 C + O2 → 2 CO + energy
Liquid iron flows from the bottom of the blast furnace and is processed into different
alloys of iron.
66 Balance the equation for the reaction of Fe2O3 and CO in your answer booklet, using
the smallest whole-number coefficients. [1]
67 Using the set of axes provided in your answer booklet, sketch a potential energy diagram
for the reaction of carbon and oxygen that produces carbon monoxide. [1]
68 What is the oxidation number of carbon in CaCO3?
[1]
69 Convert the melting point of iron metal to degrees Celsius.
[1]
Base your answers to questions 70 through 72 on the information below.
Potassium ions are essential to human health. The movement of dissolved potassium
ions, K+(aq), in and out of a nerve cell allows that cell to transmit an electrical impulse.
70 What is the total number of electrons in a potassium ion?
[1]
71 Explain, in terms of atomic structure, why a potassium ion is smaller than a potassium
atom. [1]
72 What property of potassium ions allows them to transmit an electrical impulse?
P.S./Chem.–Aug. ’04
[9]
[1]
[OVER]
Base your answers to questions 73 through 75 on the information below.
Ethene (common name ethylene) is a commercially important organic compound.
Millions of tons of ethene are produced by the chemical industry each year. Ethene is used
in the manufacture of synthetic fibers for carpeting and clothing, and it is widely used in
making polyethylene. Low-density polyethylene can be stretched into a clear, thin film that
is used for wrapping food products and consumer goods. High-density polyethylene is
molded into bottles for milk and other liquids.
Ethene can also be oxidized to produce ethylene glycol, which is used in antifreeze for
automobiles. The structural formula for ethylene glycol is:
H
H
H
C
C
H
OH OH
At standard atmospheric pressure, the boiling point of ethylene glycol is 198°C,
compared to ethene that boils at –104°C.
73 Identify the type of organic reaction by which ethene (ethylene) is made into polyethylene. [1]
74 According to the information in the reading passage, state two consumer products manufactured from ethene. [1]
75 Explain, in terms of bonding, why ethene is an unsaturated hydrocarbon.
[1]
Base your answers to questions 76 through 78 on the diagram below, which represents a voltaic cell at 298 K
and 1 atm.
Voltmeter
Wire
V
Switch S
Salt bridge
Pb electrode
Zn electrode
Half-cell 1
Half-cell 2
Pb2+(aq)
Pb2+(aq) + Zn
Zn2+(aq)
Pb + Zn2+(aq)
76 In which half-cell will oxidation occur when switch S is closed?
[1]
77 Write the balanced half-reaction equation that will occur in half-cell 1 when switch S is
closed. [1]
78 Describe the direction of electron flow between the electrodes when switch S is closed. [1]
P.S./Chem.–Aug. ’04
[10]
Base your answers to questions 79 through 81 on the information and data table below.
Indigestion may be caused by excess stomach acid (hydrochloric acid). Some products
used to treat indigestion contain magnesium hydroxide. The magnesium hydroxide
neutralizes some of the stomach acid.
The amount of acid that can be neutralized by three different brands of antacids is
shown in the data table below.
Antacid
Brand
Mass of
Antacid Tablet (g)
Volume of HCl(aq)
Neutralized (mL)
X
2.00
25.20
Y
1.20
18.65
Z
1.75
22.50
79 Based on Reference Table F, describe the solubility of magnesium hydroxide in water. [1]
80 In the space provided in your answer booklet, show a correct numerical setup for
calculating the milliliters of HCl(aq) neutralized per gram of antacid tablet for each
brand of antacid. [1]
81 Which antacid brand neutralizes the most acid per gram of antacid tablet?
P.S./Chem.–Aug. ’04
[11]
[1]
[OVER]
Base your answers to questions 82 through 85 on the reading passage below and on your knowledge of
chemistry.
A Glow in the Dark, and Scientific Peril
The [Marie and Pierre] Curies set out to study radioactivity in 1898. Their first accomplishment was to show that radioactivity was a property of atoms themselves. Scientifically,
that was the most important of their findings, because it helped other researchers refine
their understanding of atomic structure.
More famous was their discovery of polonium and radium. Radium was the most
radioactive substance the Curies had encountered. Its radioactivity is due to the large size
of the atom, which makes the nucleus unstable and prone to decay, usually to radon and
then lead, by emitting particles and energy as it seeks a more stable configuration.
Marie Curie struggled to purify radium for medical uses, including early radiation treatment for tumors. But radium’s bluish glow caught people’s fancy, and companies in the
United States began mining it and selling it as a novelty: for glow-in-the-dark light pulls, for
instance, and bogus cure-all patent medicines that actually killed people.
What makes radium so dangerous is that it forms chemical bonds in the same way as
calcium, and the body can mistake it for calcium and absorb it into the bones. Then, it can
bombard cells with radiation at close range, which may cause bone tumors or bone-marrow
damage that can give rise to anemia or leukemia.
— Denise Grady, The New York Times, October 6, 1998
82 State one risk associated with the use of radium. [1]
83 Using Reference Table N, complete the equation provided in your answer booklet for
226
the nuclear decay of 88Ra. Include both atomic number and mass number for each
particle. [1]
84 Using information from the Periodic Table, explain why radium forms chemical bonds
in the same way as calcium does. [1]
85 If a scientist purifies 1.0 gram of radium-226, how many years must pass before
only 0.50 gram of the original radium-226 sample remains unchanged? [1]
P.S./Chem.–Aug. ’04
[12]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Tuesday, August 17, 2004 — 12:30 to 3:30 p.m., only
ANSWER SHEET
■ Male ■ Female Grade
Student
..............................................
Sex:
...........
Teacher
..............................................
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
12 . . . . . . . . . . . .
23 . . . . . . . . . . .
34 . . . . . . . . . . . .
43 . . . . . . . . . . . .
2 ............
13 . . . . . . . . . . . .
24 . . . . . . . . . . .
35 . . . . . . . . . . . .
44 . . . . . . . . . . . .
3 ............
14 . . . . . . . . . . . .
25 . . . . . . . . . . .
36 . . . . . . . . . . . .
45 . . . . . . . . . . . .
4 ............
15 . . . . . . . . . . . .
26 . . . . . . . . . . .
37 . . . . . . . . . . . .
46 . . . . . . . . . . . .
5 ............
16 . . . . . . . . . . . .
27 . . . . . . . . . . .
38 . . . . . . . . . . . .
47 . . . . . . . . . . . .
6 ............
17 . . . . . . . . . . . .
28 . . . . . . . . . . .
39 . . . . . . . . . . . .
48 . . . . . . . . . . . .
7 ............
18 . . . . . . . . . . . .
29 . . . . . . . . . . .
40 . . . . . . . . . . . .
49 . . . . . . . . . . . .
8 ............
19 . . . . . . . . . . . .
30 . . . . . . . . . . .
41 . . . . . . . . . . . .
50 . . . . . . . . . . . .
9 ............
20 . . . . . . . . . . . .
31 . . . . . . . . . . .
42 . . . . . . . . . . . .
10 . . . . . . . . . . . .
21 . . . . . . . . . . . .
32 . . . . . . . . . . .
11 . . . . . . . . . . . .
22 . . . . . . . . . . . .
33 . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Thursday, January 27, 2005 — 9:15 a.m. to 12:15 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
6 Germanium is classified as a
(1) metal
(3) nonmetal
(2) metalloid
(4) noble gas
1 As an electron in an atom moves from the
ground state to the excited state, the electron
(1) gains energy as it moves to a higher energy
level
(2) gains energy as it moves to a lower energy level
(3) loses energy as it moves to a higher energy
level
(4) loses energy as it moves to a lower energy level
7 Which statement correctly describes diamond
and graphite, which are different forms of solid
carbon?
(1) They differ in their molecular structure,
only.
(2) They differ in their properties, only.
(3) They differ in their molecular structure and
properties.
(4) They do not differ in their molecular structure or properties.
2 Which subatomic particle will be attracted by a
positively charged object?
(1) proton
(3) electron
(2) neutron
(4) positron
3 Which conclusion is based on the “gold
experiment” and the resulting model of
atom?
(1) An atom is mainly empty space, and
nucleus has a positive charge.
(2) An atom is mainly empty space, and
nucleus has a negative charge.
(3) An atom has hardly any empty space,
the nucleus has a positive charge.
(4) An atom has hardly any empty space,
the nucleus has a negative charge.
foil
the
8 What is the chemical formula for copper(II)
hydroxide?
(1) CuOH
(3) Cu2(OH)
(4) Cu(OH)2
(2) CuOH2
the
the
9 What is the percent composition by mass of
aluminum in Al2(SO4)3 (gram-formula mass =
342 grams/mole)?
(1) 7.89%
(3) 20.8%
(2) 15.8%
(4) 36.0%
and
and
4 Which two particles have approximately the
same mass?
(1) proton and neutron
(2) proton and electron
(3) neutron and electron
(4) neutron and positron
10 Which statement describes a chemical property
that can be used to distinguish between compound A and compound B?
(1) A is a blue solid, and B is a white solid.
(2) A has a high melting point, and B has a low
melting point.
(3) A dissolves in water, and B does not dissolve
in water.
(4) A does not burn in air, and B does burn in
air.
5 Which element has chemical properties that are
most similar to the chemical properties
of sodium?
(1) Mg
(3) Se
(2) K
(4) Cl
P.S./Chem.–Jan. ’05
[2]
18 Which transfer of energy occurs when ice cubes
are placed in water that has a temperature of
45°C?
(1) Chemical energy is transferred from the ice
to the water.
(2) Chemical energy is transferred from the
water to the ice.
(3) Thermal energy is transferred from the ice
to the water.
(4) Thermal energy is transferred from the
water to the ice.
11 Which compound contains both ionic and covalent bonds?
(3) MgF2
(1) CaCO3
(2) PCl3
(4) CH2O
12 Which formula represents a nonpolar molecule?
(1) HCl
(3) NH3
(2) H2O
(4) CF4
13 When a lithium atom forms an Li+ ion, the lithium
atom
(1) gains a proton
(2) gains an electron
(3) loses a proton
(4) loses an electron
19 At STP, 4 liters of O2 contains the same total
number of molecules as
(3) 8 L of He
(1) 1 L of NH3
(2) 2 L of Cl2
(4) 4 L of CO2
14 Which Lewis electron-dot diagram represents a
boron atom in the ground state?
(1)
B
(3)
B
(2)
B
(4)
B
20 What is the total number of electron pairs that
are shared between the two carbon atoms in a
molecule of ethyne?
(1) 1
(3) 3
(2) 2
(4) 4
21 Which pair of compounds are isomers?
(1) NO2 and N2O4
(2) P2O5 and P4O10
(3) HCOOH and CH3COOH
(4) CH3OCH3 and C2H5OH
15 A sample is prepared by completely dissolving
10.0 grams of NaCl in 1.0 liter of H2O. Which
classification best describes this sample?
(1) homogeneous compound
(2) homogeneous mixture
(3) heterogeneous compound
(4) heterogeneous mixture
22 Which organic compound is unsaturated?
(1) 2-methylbutane
(3) 2-hexanol
(2) 2-chloropropane
(4) 2-pentene
16 Which form of energy is converted to thermal
energy when propane burns in air?
(1) electromagnetic
(3) electrical
(2) nuclear
(4) chemical
23 Which change in oxidation number indicates
oxidation?
(1) –1 to +2
(3) +2 to –3
(2) –1 to –2
(4) +3 to +2
17 Which physical changes are endothermic?
(1) melting and freezing
(2) melting and evaporating
(3) condensation and sublimation
(4) condensation and deposition
P.S./Chem.–Jan. ’05
[3]
[OVER]
28 Which reaction is an example of natural transmutation?
24 Given the redox reaction:
Cr3+ + Al → Cr + Al3+
As the reaction takes place, there is a transfer of
(1)
(2)
(3)
(4)
electrons from Al to Cr 3+
electrons from Cr3+ to Al
protons from Al to Cr 3+
protons from Cr 3+ to Al
26 According to Reference Table M, what is the
color of the indicator methyl orange in a solution that has a pH of 2?
(1) blue
(3) orange
(2) yellow
(4) red
(2)
27
13Al
(3)
238U
92
(4)
239Pu
94
4
→ 235
92U + 2He
1
+ 24He → 30
15P + 0n
0
+ 01n → 239
94Pu + 2 –1e
90
1
+ 10n → 147
56Ba + 38Sr + 30n
30 Which change takes place in a nuclear fusion
reaction?
(1) Matter is converted to energy.
(2) Energy is converted to matter.
(3) Ionic bonds are converted to covalent
bonds.
(4) Covalent bonds are converted to ionic
bonds.
27 Given the reaction:
NH3 + HCl → NH4Cl
In this reaction, ammonia molecules (NH3) act
as a base because they
accept hydrogen ions (H+)
accept hydroxide ions (OH–)
donate hydrogen ions (H+)
donate hydroxide ions (OH–)
P.S./Chem.–Jan. ’05
239 Pu
94
29 Which statement best describes gamma radiation?
(1) It has a mass of 1 and a charge of 1.
(2) It has a mass of 0 and a charge of –1.
(3) It has a mass of 0 and a charge of 0.
(4) It has a mass of 4 and a charge of +2.
25 The compound HNO3 can be described as an
(1) Arrhenius acid and an electrolyte
(2) Arrhenius acid and a nonelectrolyte
(3) Arrhenius base and an electrolyte
(4) Arrhenius base and a nonelectrolyte
(1)
(2)
(3)
(4)
(1)
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
36 How many electrons are in an Fe2+ ion?
(1) 24
(3) 28
(2) 26
(4) 56
31 What is the total number of neutrons in the
nucleus of a neutral atom that has 19 electrons
and a mass number of 39?
(1) 19
(3) 39
(2) 20
(4) 58
37 A substance that does not conduct electricity as a
solid but does conduct electricity when melted is
most likely classified as
(1) an ionic compound
(2) a molecular compound
(3) a metal
(4) a nonmetal
32 An unknown element X can form a compound
with the formula XBr3. In which group on the
Periodic Table would element X be found?
(1) 1
(3) 13
(2) 2
(4) 14
33 As the elements in Group 17 on the Periodic
Table are considered from top to bottom, what
happens to the atomic radius and the metallic
character of each successive element?
(1) The atomic radius and the metallic character both increase.
(2) The atomic radius increases and the metallic character decreases.
(3) The atomic radius decreases and the metallic character increases.
(4) The atomic radius and the metallic character both decrease.
38 According to Reference Table H, what is the
boiling point of ethanoic acid at 80 kPa?
(1) 28°C
(3) 111°C
(2) 100°C
(4) 125°C
39 Which particle diagram represents one pure
substance, only?
34 Which pair of compounds has the same empirical formula?
(1) C2H2 and C6H6
(2) C2H6 and C3H8
(3) CH3OH and C2H5OH
(4) CH3CHO and CH3COOH
35 Which equation shows a conservation of mass?
(1) Na + Cl2 → NaCl
(2) Al + Br2 → AlBr3
(3) H2O → H2 + O2
(4) PCl5 → PCl3 + Cl2
P.S./Chem.–Jan. ’05
[5]
(1)
(3)
(2)
(4)
[OVER]
45 Which half-reaction can occur at the anode in a
voltaic cell?
(1) Ni2+ + 2e– → Ni
(3) Zn → Zn2+ + 2e–
(2) Sn + 2e– → Sn2+
(4) Fe3+ → Fe2+ + e–
40 A sample of helium gas has a volume of
900. milliliters and a pressure of 2.50 atm at
298 K. What is the new pressure when the temperature is changed to 336 K and the volume is
decreased to 450. milliliters?
(1) 0.177 atm
(3) 5.64 atm
(2) 4.43 atm
(4) 14.1 atm
46 Given the reaction:
Ba(OH)2(aq) + H2SO4(aq) →
BaSO4(s) + 2 H2O() + energy
41 Given the particle diagram:
As the barium hydroxide solution is added to the
solution of sulfuric acid, the electrical conductivity of the acid solution decreases because the
Key
atom
(1)
(2)
(3)
(4)
At 101.3 kPa and 298 K, which element could
this diagram represent?
(1) Rn
(2) Xe
(3) Ag
(4) Kr
47 Which chemical equation represents the reaction
of an Arrhenius acid and an Arrhenius base?
(1) HC2H3O2(aq) + NaOH(aq) →
NaC2H3O2(aq) + H2O()
(2) C3H8(g) + 5 O2(g) → 3 CO2(g) + 4 H2O()
(3) Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g)
(4) BaCl2(aq) + Na2SO4(aq) →
BaSO4(s) + 2 NaCl(aq)
42 For most atoms with an atomic number less
than 20, nuclear stability occurs when the ratio
of neutrons to protons is 1:1. Which of the following atoms would be most likely to have an
unstable nucleus?
(1) 42He
(3) 167N
(2)
12 C
6
(4)
24Mg
12
48 Based on Reference Table F, which of these saturated solutions has the lowest concentration of
dissolved ions?
(1) NaCl(aq)
(3) NiCl2(aq)
(2) MgCl2(aq)
(4) AgCl(aq)
43 Which of these changes produces the greatest
increase in entropy?
(1) CaCO3(s) → CaO(s) + CO2(g)
(2) 2 Mg(s) + O2(g) → 2 MgO(s)
(3) H2O(g) → H2O()
(4) CO2(g) → CO2(s)
49 Based on Reference Table N, what fraction of a
radioactive 90Sr sample would remain unchanged
after 56.2 years?
44 Given the structural formula:
H
H
H
C
C
H
N
H
(1)
O
C OH
(2)
P.S./Chem.–Jan. ’05
1
2
1
4
(3)
(4)
1
8
1
16
50 Given the nuclear equation:
19 Ne → X + 19F
10
9
H
Which particle is represented by X?
This structural formula represents a molecule of
(1) an aldehyde
(2) an ester
volume of the reaction mixture increases
temperature of the reaction mixture decreases
concentration of ions increases
concentration of ions decreases
(1) alpha
(2) beta
(3) a ketone
(4) an amino acid
[6]
(3) neutron
(4) positron
Part B–2
Answer all questions in this part.
Directions (51–65): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 51 through 53 on your knowledge of chemical bonding and on the Lewis
electron-dot diagrams of H2S, CO2, and F2 below.
H S
H
O C O
F F
51 Which atom, when bonded as shown, has the same electron configuration as an atom
of argon? [1]
52 Explain, in terms of structure and/or distribution of charge, why CO2 is a nonpolar
molecule. [1]
– bond in CO is more polar than the
53 Explain, in terms of electronegativity, why a C–O
2
F–F bond in F2. [1]
Temperature (K)
Base your answers to questions 54 and 55 on the heating curve below, which represents a substance
starting as a solid below its melting point and being heated at a constant rate over a period of time.
F
D
E
B
C
A
Time (min)
54 What is happening to the average kinetic energy of the particles during segment BC ? [1]
55 How does this heating curve illustrate that the heat of vaporization is greater than the
heat of fusion? [1]
P.S./Chem.–Jan. ’05
[7]
[OVER]
Potential Energy
Base your answers to questions 56 through 58 on the potential energy diagram and the equation below.
B
(2)
(3)
A
(4)
(1)
Reaction Coordinate
2 C(s) + H 2(g) + 227.4 kJ → C 2H 2(g)
56 The letter B represents which chemical formula or formulas in the equation?
57 If 682.2 kilojoules are absorbed, how many moles of C2H2(g) are produced?
58 Describe how the potential energy diagram will change if a catalyst is added.
[1]
[1]
[1]
Base your answers to questions 59 and 60 on the condensed structural formula below.
CH3CH2CHCH2
59 In the space provided in your answer booklet, draw the structural formula for this
compound. [1]
60 The formula below represents a product formed when HCl reacts with
CH3CH2CHCH2.
H
H
H H
H
C
C
C
C
H Cl
H
H
What is an IUPAC name for this product?
P.S./Chem.–Jan. ’05
[8]
[1]
H
61 Given the equation:
catalyst
butanoic acid + 1-pentanol
water + X
To which class of organic compounds does product X belong?
[1]
62 Identify the homologous series of hydrocarbons to which CH3CHCH2 belongs.
[1]
Base your answers to questions 63 through 65 on the information below.
In a titration experiment, a student uses a 1.4 M HBr(aq) solution and the indicator
phenolphthalein to determine the concentration of a KOH(aq) solution. The data for
trial 1 is recorded in the table below.
Trial 1
Buret Readings
HBr(aq)
KOH(aq)
Initial volume (mL)
7.50
11.00
Final volume (mL)
22.90
33.10
Volume used (mL)
15.40
22.10
63 In the space provided in your answer booklet, show a correct numerical setup for
calculating the molarity of the KOH(aq) solution for trial 1. [1]
64 Why is it better to use several trials of a titration rather than one trial to determine the
molarity of a solution of an unknown concentration? [1]
65 In a second trial of this experiment, the molarity of KOH(aq) was determined to be 0.95 M.
The actual molarity was 0.83 M. What is the percent error in the second trial? [1]
P.S./Chem.–Jan. ’05
[9]
[OVER]
Part C
Answer all questions in this part.
Directions (66–84): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 66 and 67 on the information below.
Naturally occurring elemental carbon is a mixture of isotopes. The percent composition
of the two most abundant isotopes is listed below.
• 98.93% of the carbon atoms have a mass of 12.00 atomic mass units.
• 1.07% of the carbon atoms have a mass of 13.00 atomic mass units.
66 In the space provided in your answer booklet, show a correct numerical setup for
calculating the average atomic mass of carbon. [1]
67 Describe, in terms of subatomic particles found in the nucleus, one difference between
the nuclei of carbon-12 atoms and the nuclei of carbon-13 atoms. The response must
include both isotopes. [1]
Base your answers to questions 68 and 69 on the information below.
A scientist in a chemistry laboratory determined the molecular formulas for two
compounds containing nitrogen and oxygen to be NO2 and N2O5.
68 Write an IUPAC name for the compound N2O5.
[1]
69 In the space provided in your answer booklet, show a correct numerical setup for
calculating the percent composition by mass of oxygen in NO2. [1]
P.S./Chem.–Jan. ’05
[10]
Base your answers to questions 70 through 72 on the information below.
In a laboratory experiment, 10.00 grams of an unknown solid is added to 100.0 milliliters of water and the temperature of the resulting solution is measured over several
minutes, as recorded in the table below.
Data Table
Time
(minutes)
Temperature
(°C)
0
24.0
0.5
28.5
1.0
31.0
1.5
34.5
2.0
41.0
2.5
45.5
3.0
46.5
70 On the grid provided in your answer booklet, mark an appropriate scale on the axis labeled
“Temperature (°C).” An appropriate scale is one that allows a trend to be seen. [1]
71 Plot the data from the data table. Circle and connect the points. [1]
Example:
72 Given the statement:
The unknown solid is either sodium hydroxide or lithium bromide, and
both of these compounds dissolve in water exothermically.
a Explain how the experimental data support the statement. [1]
b State specific information from Reference Table I to support the statement.
P.S./Chem.–Jan. ’05
[11]
[1]
[OVER]
Base your answers to questions 73 through 76 on the information below.
Figure 1
50.0 g Cu(s)
at 100.0°C
In a laboratory investigation, a 50.0-gram sample
of copper is at 100.0°C in a boiling water bath.
Figure 2
100.0 g H2O( )
at 23.2°C
A Styrofoam cup with a lid is used as a calorimeter.
The cup contains 100.0 grams of distilled water at
23.2°C.
Calorimeter
Figure 3
The hot copper is poured into the cup of water, and
the cup is quickly covered with the lid.
Calorimeter
Figure 4
A thermometer is inserted through the lid. The copper
and water are gently stirred in the cup. The temperature is
checked periodically. The highest temperature noted is
26.3°C.
Calorimeter
P.S./Chem.–Jan. ’05
[12]
73 In terms of energy flow, explain why the temperature of the water in the calorimeter
increases. [1]
74 Using the information given, complete the data table provided in your answer booklet.
[1]
75 In the space provided in your answer booklet, show a correct numerical setup for
calculating the number of joules of heat gained by the water. [1]
76 In this investigation, the change in heat of the copper is greater than the change in heat
of the water. What error could account for this apparent violation of the Law of
Conservation of Energy? Do not use human error as part of the answer. [1]
Base your answers to questions 77 through 79 on the information below.
Two alcohols that are used in our everyday lives are rubbing alcohol and ethylene
glycol. Rubbing alcohol is used as an antiseptic. Ethylene glycol is the main ingredient in
antifreeze, which is used in automobile cooling systems.
77 Explain, in terms of molecular polarity, why rubbing alcohol, 2-propanol, is soluble in
water. [1]
78 What is the gram-formula mass of ethylene glycol, C2H4(OH)2?
[1]
79 In the space provided in your answer booklet, show a correct numerical setup for
calculating the total number of moles of ethylene glycol needed to prepare 2.50 liters
of a 10.0 M solution. [1]
Base your answers to questions 80 and 81 on the information below.
The outer structure of the Statue of Liberty is made of copper metal. The framework
is made of iron. Over time, a thin green layer (patina) forms on the copper surface.
80 When copper oxidized to form this patina layer, the copper atoms became copper(II)
ions (Cu2+). Write a balanced half-reaction for this oxidation of copper. [1]
81 Where the iron framework came in contact with the copper surface, a reaction
occurred in which iron was oxidized. Using information from Reference Table J, explain
why the iron was oxidized. [1]
P.S./Chem.–Jan. ’05
[13]
[OVER]
Base your answers to questions 82 through 84 on the information below, the Reference Tables for Physical
Setting/Chemistry, and your knowledge of chemistry.
Radioactivity and radioactive isotopes have the potential for both benefiting and
harming living organisms. One use of radioactive isotopes is in radiation therapy as a treatment for cancer. Cesium-137 is sometimes used in radiation therapy.
A sample of cesium-137 was left in an abandoned clinic in Brazil in 1987. Cesium-137
gives off a blue glow because of its radioactivity. The people who discovered the sample
were attracted by the blue glow and had no idea of any danger. Hundreds of people were
treated for overexposure to radiation, and four people died.
82 Using Reference Table N, complete the equation provided in your answer booklet for
the radioactive decay of 137
55Cs. Include both atomic number and mass number for each
particle. [1]
83 If 12.5 grams of the original sample of cesium-137 remained after 90.69 years, what was
the mass of the original sample? [1]
84 Suppose a 40-gram sample of iodine-131 and a 40-gram sample of cesium-137 were
both abandoned in the clinic in 1987. Explain why the sample of iodine-131 would not
pose as great a radiation risk to people today as the sample of cesium-137 would. [1]
P.S./Chem.–Jan. ’05
[14]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Thursday, January 27, 2005 — 9:15 a.m. to 12:15 p.m., only
ANSWER SHEET
■ Male ■ Female Grade . . . . . . . . . . . .
Student . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sex:
Teacher . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part A Score
Part B–1 Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Wednesday, June 22, 2005 — 1:15 to 4:15 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
The use of any communications device is strictly prohibited when taking this
examination. If you use any communications device, no matter how briefly, your
examination will be invalidated and no score will be calculated for you.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–33): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
7 Which element is malleable and conducts electricity?
(1) iron
(3) sulfur
(2) iodine
(4) phosphorus
1 In the modern wave-mechanical model of the
atom, the orbitals are regions of the most probable location of
(1) protons
(3) electrons
(2) neutrons
(4) positrons
8 At STP, solid carbon can exist as graphite or as
diamond. These two forms of carbon have
(1) the same properties and the same crystal
structures
(2) the same properties and different crystal
structures
(3) different properties and the same crystal
structures
(4) different properties and different crystal
structures
2 Compared to a proton, an electron has
(1) a greater quantity of charge and the same sign
(2) a greater quantity of charge and the opposite
sign
(3) the same quantity of charge and the same sign
(4) the same quantity of charge and the opposite
sign
3 Which two notations represent atoms that are
isotopes of the same element?
(1)
(2)
121 Sn
50
121 Sn
50
and 119
50 Sn
(3)
and 121
50 Sn
(4)
9 What is the formula of titanium(II) oxide?
(1) TiO
(3) Ti2O
(2) TiO2
(4) Ti2O3
19 O and 19 F
8
9
39 Cl and 39 K
17
19
4 The elements in Period 5 on the Periodic Table
are arranged from left to right in order of
(1) decreasing atomic mass
(2) decreasing atomic number
(3) increasing atomic mass
(4) increasing atomic number
10 Which substance can be decomposed by a
chemical change?
(1) calcium
(3) copper
(2) potassium
(4) ammonia
11 As a chlorine atom becomes a negative ion, the
atom
(1) gains an electron and its radius increases
(2) gains an electron and its radius decreases
(3) loses an electron and its radius increases
(4) loses an electron and its radius decreases
5 Which list of elements contains a metal, a
metalloid, and a nonmetal?
(1) Zn, Ga, Ge
(3) Cd, Sb, I
(2) Si, Ge, Sn
(4) F, Cl, Br
6 An example of a physical property of an element
is the element’s ability to
(1) react with an acid
(2) react with oxygen
(3) form a compound with chlorine
(4) form an aqueous solution
P.S./Chem.–June ’05
12 Based on Reference Table S, the atoms of which
of these elements have the strongest attraction
for electrons in a chemical bond?
(1) N
(3) P
(2) Na
(4) Pt
[2]
19 Adding a catalyst to a chemical reaction results
in
(1) a decrease in activation energy and a decrease
in the reaction rate
(2) a decrease in activation energy and an increase
in the reaction rate
(3) an increase in activation energy and a decrease
in the reaction rate
(4) an increase in activation energy and an
increase in the reaction rate
13 Which terms are used to identify pure substances?
(1) an element and a mixture
(2) an element and a compound
(3) a solution and a mixture
(4) a solution and a compound
14 The solubility of KClO3(s) in water increases as
the
(1) temperature of the solution increases
(2) temperature of the solution decreases
(3) pressure on the solution increases
(4) pressure on the solution decreases
20 Systems in nature tend to undergo changes
toward
(1) lower energy and lower entropy
(2) lower energy and higher entropy
(3) higher energy and lower entropy
(4) higher energy and higher entropy
15 Compared to a 0.1 M aqueous solution of NaCl,
a 0.8 M aqueous solution of NaCl has a
(1) higher boiling point and a higher freezing
point
(2) higher boiling point and a lower freezing
point
(3) lower boiling point and a higher freezing
point
(4) lower boiling point and a lower freezing point
21 Which element has atoms that can bond with
each other to form long chains or rings?
(1) carbon
(3) oxygen
(2) nitrogen
(4) fluorine
22 Which formula represents an unsaturated
hydrocarbon?
(1) C2H6
(3) C5H8
(2) C3H8
(4) C6H14
16 The kinetic molecular theory assumes that the
particles of an ideal gas
(1) are in random, constant, straight-line motion
(2) are arranged in a regular geometric pattern
(3) have strong attractive forces between them
(4) have collisions that result in the system losing
energy
23 Given the structural formula:
H
C
17 In which process does a solid change directly
into a vapor?
(1) condensation
(3) deposition
(2) sublimation
(4) solidification
C
H
H
C
H
H
What is the IUPAC name of this compound?
(1) propane
(2) propene
18 Which statement must be true about a chemical
system at equilibrium?
(1) The forward and reverse reactions stop.
(2) The concentration of reactants and products
are equal.
(3) The rate of the forward reaction is equal to
the rate of the reverse reaction.
(4) The number of moles of reactants is equal to
the number of moles of product.
P.S./Chem.–June ’05
H
(3) propanone
(4) propanal
24 What is the oxidation state of nitrogen in NaNO2?
(1) +1
(3) +3
(2) +2
(4) +4
[3]
[OVER]
30 Which equation represents a transmutation
reaction?
25 The three isomers of pentane have different
(1) formula masses
(2) molecular formulas
(3) empirical formulas
(4) structural formulas
(1)
(2)
239 U → 239 U + 0 γ
92
92
0
14 C → 14 N + 0e
6
7
–1
(3) C3H8 + 5O2 → 3CO2 + 4H2O
26 Where does oxidation occur in an electrochemical cell?
(1) at the cathode in both an electrolytic cell and
a voltaic cell
(2) at the cathode in an electrolytic cell and at the
anode in a voltaic cell
(3) at the anode in both an electrolytic cell and a
voltaic cell
(4) at the anode in an electrolytic cell and at the
cathode in a voltaic cell
(4) nC2H4
(–C2H4–)n
31 Which equation represents positron decay?
(1)
(2)
(3)
(4)
87 Rb → 0e + 87Sr
37
–1
38
227U → 223 Th + 4He
92
90
2
27 Al + 4He → 30P + 1n
13
2
15
0
11C → 0 e + 11B
6
+1
5
32 Which equation represents a fusion reaction?
27 Which formula represents an electrolyte?
(1) CH3OCH3
(3) CH3COOH
(2) CH3OH
(4) C2H5CHO
(1) H2O(g) → H2O()
(2) C(s) + O2(g) → CO2(g)
(3) 21H + 31H → 42He + 10n
(4)
28 When an Arrhenius acid dissolves in water, the
only positive ion in the solution is
(3) Na+
(1) H+
+
(2) Li
(4) K+
235U
92
91
1
+ 10n → 142
56Ba + 36Kr + 30n
Note that question 33 has only three choices.
33 An electron in an atom moves from the ground
state to an excited state when the energy of the
electron
(1) decreases
(2) increases
(3) remains the same
29 What is the half-life and decay mode of Rn-222?
(1) 1.91 days and alpha decay
(2) 1.91 days and beta decay
(3) 3.82 days and alpha decay
(4) 3.82 days and beta decay
P.S./Chem.–June ’05
catalyst
[4]
Part B–1
Answer all questions in this part.
Directions (34–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
34 Which symbol represents a particle that has the
same total number of electrons as S2–?
(3) Se2–
(1) O2–
(2) Si
(4) Ar
39 A sample of a substance containing only
magnesium and chlorine was tested in the
laboratory and was found to be composed of
74.5% chlorine by mass. If the total mass of the
sample was 190.2 grams, what was the mass of
the magnesium?
(1) 24.3 g
(3) 70.9 g
(2) 48.5 g
(4) 142 g
35 The data table below shows elements Xx, Yy,
and Zz from the same group on the Periodic
Table.
Element
Atomic Mass
(atomic mass unit)
Atomic Radius
(pm)
Xx
69.7
141
Yy
114.8
?
Zz
204.4
171
40 Which molecule contains a nonpolar covalent
bond?
O
O
Br Br
(1)
(3)
CI
C
What is the most likely atomic radius of element
Yy?
(1) 103 pm
(2) 127 pm
C
O
CI
C
CI
CI
(3) 166 pm
(4) 185 pm
(2)
(4)
41 According to Reference Table G, which substance
forms an unsaturated solution when 80 grams of
the substance is dissolved in 100 grams of H2O at
10°C?
(1) KI
(3) NaNO3
(2) KNO3
(4) NaCl
36 Which substance has a chemical formula with
the same ratio of metal ions to nonmetal ions as
in potassium sulfide?
(1) sodium oxide
(2) sodium chloride
(3) magnesium oxide
(4) magnesium chloride
42 What is the concentration of a solution, in parts
per million, if 0.02 gram of Na3PO4 is dissolved
in 1000 grams of water?
(1) 20 ppm
(3) 0.2 ppm
(2) 2 ppm
(4) 0.02 ppm
37 The molecular formula of glucose is C6H12O6.
What is the empirical formula of glucose?
(1) CHO
(3) C6H12O6
(2) CH2O
(4) C12H24O12
38 According to Reference Table F, which of these
compounds is the least soluble in water?
(1) K2CO3
(2) KC2H3O2
P.S./Chem.–June ’05
(3) Ca3(PO4)2
(4) Ca(NO3)2
[5]
[OVER]
46 At STP, fluorine is a gas and iodine is a solid.
This observation can be explained by the fact
that fluorine has
(1) weaker intermolecular forces of attraction
than iodine
(2) stronger intermolecular forces of attraction
than iodine
(3) lower average kinetic energy than iodine
(4) higher average kinetic energy than iodine
43 Given the simple representations for atoms of
two elements:
= an atom of an element
= an atom of a different element
Which particle diagram represents molecules of
only one compound in the gaseous phase?
47 Given the structural formula:
H H
H H
H C C O C C H
(1)
H H
(3)
H H
The compound represented by this formula can
be classified as an
(1) organic acid
(2) ether
(2)
48 Sulfuric acid, H2SO4(aq), can be used to neutralize barium hydroxide, Ba(OH)2(aq). What is
the formula for the salt produced by this
neutralization?
(1) BaS
(3) BaSO3
(2) BaSO2
(4) BaSO4
(4)
44 Given the balanced equation:
KNO3(s) + 34.89 kJ
H2O
K+(aq) + NO3–(aq)
Which statement best describes this process?
(1)
(2)
(3)
(4)
49 Given the balanced ionic equation:
It is endothermic and entropy increases.
It is endothermic and entropy decreases.
It is exothermic and entropy increases.
It is exothermic and entropy decreases.
Zn(s) + Cu2+(aq) → Zn2+(aq) + Cu(s)
Which equation represents the oxidation halfreaction?
(1)
(2)
(3)
(4)
45 A 1.0-gram piece of zinc reacts with 5 milliliters
of HCl(aq). Which of these conditions of concentration and temperature would produce the
greatest rate of reaction?
(1) 1.0 M HCl(aq) at 20.°C
(2) 1.0 M HCl(aq) at 40.°C
(3) 2.0 M HCl(aq) at 20.°C
(4) 2.0 M HCl(aq) at 40.°C
P.S./Chem.–June ’05
(3) ester
(4) aldehyde
Zn(s) + 2e– → Zn2+(aq)
Zn(s) → Zn2+(aq) + 2e–
Cu2+(aq) → Cu(s) + 2e–
Cu2+(aq) + 2e– → Cu(s)
50 In which solution will thymol blue indicator
appear blue?
(1) 0.1 M CH3COOH (3) 0.1 M HCl
(2) 0.1 M KOH
(4) 0.1 M H2SO4
[6]
Part B–2
Answer all questions in this part.
Directions (51–64): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 51 and 52 on the diagram below, which represents an atom of magnesium-26
in the ground state.
Mg-26 nucleus
2
8
2
51 What is the total number of valence electrons in an atom of Mg-26 in the ground state? [1]
52 On the diagram in your answer booklet, write an appropriate number of electrons in
each shell to represent a Mg-26 atom in an excited state. Your answer may include
additional shells. [1]
53 Explain, in terms of atomic structure, why germanium is chemically similar to silicon. [1]
54 Given the balanced equation:
4Al(s) + 3O2(g) → 2Al2O3(s)
What is the total number of moles of O2(g) that must react completely with 8.0 moles
of Al(s) in order to form Al2O3(s)? [1]
Base your answers to questions 55 and 56 on the balanced equation below.
2Na(s) + Cl2(g) → 2NaCl(s)
55 In the box in your answer booklet, draw a Lewis electron-dot diagram for a molecule
of chlorine, Cl2. [1]
56 Explain, in terms of electrons, why the bonding in NaCl is ionic. [1]
P.S./Chem.–June ’05
[7]
[OVER]
Base your answers to questions 57 and 58 on the information below.
Given the reaction at equilibrium:
2NO2(g) + 7H2(g)
2NH3(g) + 4H2O(g) + 1127 kJ
57 On the diagram in your answer booklet, complete the potential energy diagram for the
forward reaction. Be sure your drawing shows the activation energy and the potential
energy of the products. [2]
58 Explain, in terms of Le Chatelier’s principle, why the concentration of NH3(g) decreases
when the temperature of the equilibrium system increases. [1]
Base your answers to questions 59 and 60 on the information below.
Given the reaction between 1-butene and chlorine gas:
C4H8 + Cl2 → C4H8Cl2
59 Which type of chemical reaction is represented by this equation? [1]
60 In the space in your answer booklet, draw the structural formula of the product
1,2-dichlorobutane. [1]
P.S./Chem.–June ’05
[8]
Base your answers to questions 61 through 64 on the information below, which relates the numbers of
neutrons and protons for specific nuclides of C, N, Ne, and S.
Number of Neutrons Versus
Number of Protons in Selected Nuclides
20
This line connects points
where the neutron-to-proton
ratio is 1:1
S
Number of Neutrons
15
10
N
Ne
C
5
0
5
10
15
Number of Protons
20
61 Using the point plotted on the graph for neon, complete the table in your answer
booklet. [1]
62 Explain, in terms of atomic particles, why S-32 is a stable nuclide.
[1]
63 Using the point plotted on the graph for nitrogen, what is the neutron-to-proton ratio
of this nuclide? [1]
64 Based on Reference Table N, complete the decay equation for N-16 in your answer
booklet. [1]
P.S./Chem.–June ’05
[9]
[OVER]
Part C
Answer all questions in this part.
Directions (65–83): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
65 In the early 1900s, experiments were conducted to determine the structure of the
atom. One of these experiments involved bombarding gold foil with alpha particles.
Most alpha particles passed directly through the foil. Some, however, were deflected at
various angles. Based on this alpha particle experiment, state two conclusions that were
made concerning the structure of an atom. [2]
Base your answers to questions 66 through 70 on the information below.
A substance is a solid at 15°C. A student heated a sample of the solid substance and
recorded the temperature at one-minute intervals in the data table below.
Time (min)
0
1
2
3
4
5
6
7
8
9
10
11
12
Temperature (°C)
15
32
46
53
53
53
53
53
53
53
53
60
65
66 On the grid in your answer booklet, mark an appropriate scale on the axis labeled
“Temperature (°C).” An appropriate scale is one that allows a trend to be seen. [1]
67 Plot the data from the data table. Circle and connect the points. [1]
Example:
68 Based on the data table, what is the melting point of this substance? [1]
69 What is the evidence that the average kinetic energy of the particles of this substance
is increasing during the first three minutes? [1]
70 The heat of fusion for this substance is 122 joules per gram. How many joules of heat
are needed to melt 7.50 grams of this substance at its melting point? [1]
P.S./Chem.–June ’05
[10]
Base your answers to questions 71 through 73 on the diagram of a voltaic cell and the balanced ionic
equation below.
Wire
Wire
V
Voltmeter
Salt
bridge
Mg(s)
Mg2+(aq)
Ni(s)
Ni2+(aq)
Mg(s) + Ni2+(aq)
Mg2+(aq) + Ni(s)
71 What is the total number of moles of electrons needed to completely reduce 6.0 moles
of Ni2+(aq) ions? [1]
72 Identify one metal from Reference Table J that is more easily oxidized than Mg(s). [1]
73 Explain the function of the salt bridge in the voltaic cell.
[1]
Base your answers to questions 74 through 76 on the passage below.
Acid rain is a problem in industrialized countries around the world. Oxides of sulfur
and nitrogen are formed when various fuels are burned. These oxides dissolve in
atmospheric water droplets that fall to earth as acid rain or acid snow.
While normal rain has a pH between 5.0 and 6.0 due to the presence of dissolved
carbon dioxide, acid rain often has a pH of 4.0 or lower. This level of acidity can damage trees
and plants, leach minerals from the soil, and cause the death of aquatic animals and plants.
If the pH of the soil is too low, then quicklime, CaO, can be added to the soil to
increase the pH. Quicklime produces calcium hydroxide when it dissolves in water.
74 Balance the neutralization equation in your answer booklet, using the smallest wholenumber coefficients. [1]
75 A sample of wet soil has a pH of 4.0. After the addition of quicklime, the H+ ion
concentration of the soil is
1
100
of the original H+ ion concentration of the soil. What is
the new pH of the soil sample? [1]
76 Samples of acid rain are brought to a laboratory for analysis. Several titrations are
performed and it is determined that a 20.0-milliliter sample of acid rain is neutralized with
6.50 milliliters of 0.010 M NaOH. What is the molarity of the H+ ions in the acid rain? [1]
P.S./Chem.–June ’05
[11]
[OVER]
Base your answers to questions 77 through 79 on the information and diagrams below.
Cylinder A contains 22.0 grams of CO2(g) and cylinder B contains N2(g). The volumes,
pressures, and temperatures of the two gases are indicated under each cylinder.
Cylinder A
Cylinder B
CO2(g)
N2(g)
V = 12.3 L
P = 1.0 atm
T = 300. K
V = 12.3 L
P = 1.0 atm
T = 300. K
77 What is the total number of moles of CO2(g) in cylinder A? [1]
78 Explain why the number of molecules of N2(g) in cylinder B is the same as the number
of molecules of CO2(g) in cylinder A. [1]
79 The temperature of the CO2(g) is increased to 450. K and the volume of cylinder A
remains constant. In the space in your answer booklet, show a correct numerical setup
for calculating the new pressure of the CO2(g) in cylinder A. [1]
P.S./Chem.–June ’05
[12]
Base your answers to questions 80 through 83 on the information and diagram below and on your
knowledge of chemistry.
Crude oil is a mixture of many hydrocarbons that have different numbers of carbon
atoms. The use of a fractionating tower allows the separation of this mixture based on the
boiling points of the hydrocarbons.
To begin the separation process, the crude oil is heated to about 400°C in a furnace,
causing many of the hydrocarbons of the crude oil to vaporize. The vaporized mixture
is pumped into a fractionating tower that is usually more than 30 meters tall. The
temperature of the tower is highest at the bottom. As vaporized samples of hydrocarbons
travel up the tower, they cool and condense. The liquid hydrocarbons are collected on trays
and removed from the tower. The diagram below illustrates the fractional distillation of the
crude oil and the temperature ranges in which the different hydrocarbons condense.
Distillation of Crude Oil
Less than 40°C
Hydrocarbons with
1 to 4 carbon atoms
40°C – 200°C
Hydrocarbons with
5 to 12 carbon atoms
Decreasing temperature
200°C – 300°C
Hydrocarbons with
12 to 16 carbon atoms
250°C – 350°C
Hydrocarbons with
15 to 18 carbon atoms
300°C – 370°C
Hydrocarbons with
16 to 20 carbon atoms
Greater than 370°C
Crude
oil
Furnace
Fractionating tower
Hydrocarbons with
more than
20 carbon atoms
80 State the trend between the boiling point of the hydrocarbons contained in the crude
oil and the number of carbon atoms in these molecules. [1]
81 Describe the relationship between the strength of the intermolecular forces and the
number of carbon atoms in the different hydrocarbon molecules. [1]
82 Write an IUPAC name of one saturated hydrocarbon that leaves the fractionating tower
at less than 40°C. [1]
83 How many hydrogen atoms are present in one molecule of octane? [1]
P.S./Chem.–June ’05
[13]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Wednesday, June 22, 2005 — 1:15 to 4:15 p.m., only
ANSWER SHEET
■ Male ■ Female Grade
Student
..............................................
Sex:
...........
Teacher
..............................................
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
12 . . . . . . . . . . . .
23 . . . . . . . . . . .
34 . . . . . . . . . . . .
43 . . . . . . . . . . . .
2 ............
13 . . . . . . . . . . . .
24 . . . . . . . . . . .
35 . . . . . . . . . . . .
44 . . . . . . . . . . . .
3 ............
14 . . . . . . . . . . . .
25 . . . . . . . . . . .
36 . . . . . . . . . . . .
45 . . . . . . . . . . . .
4 ............
15 . . . . . . . . . . . .
26 . . . . . . . . . . .
37 . . . . . . . . . . . .
46 . . . . . . . . . . . .
5 ............
16 . . . . . . . . . . . .
27 . . . . . . . . . . .
38 . . . . . . . . . . . .
47 . . . . . . . . . . . .
6 ............
17 . . . . . . . . . . . .
28 . . . . . . . . . . .
39 . . . . . . . . . . . .
48 . . . . . . . . . . . .
7 ............
18 . . . . . . . . . . . .
29 . . . . . . . . . . .
40 . . . . . . . . . . . .
49 . . . . . . . . . . . .
8 ............
19 . . . . . . . . . . . .
30 . . . . . . . . . . .
41 . . . . . . . . . . . .
50 . . . . . . . . . . . .
9 ............
20 . . . . . . . . . . . .
31 . . . . . . . . . . .
42 . . . . . . . . . . . .
10 . . . . . . . . . . . .
21 . . . . . . . . . . . .
32 . . . . . . . . . . .
11 . . . . . . . . . . . .
22 . . . . . . . . . . . .
33 . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Tuesday, August 16, 2005 — 12:30 to 3:30 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
The use of any communications device is strictly prohibited when taking this
examination. If you use any communications device, no matter how briefly, your
examination will be invalidated and no score will be calculated for you.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
6 The elements located in the lower left corner of
the Periodic Table are classified as
(1) metals
(3) metalloids
(2) nonmetals
(4) noble gases
1 Which subatomic particle has a negative charge?
(1) proton
(3) neutron
(2) electron
(4) positron
2 Which statement best describes the nucleus of an
aluminum atom?
(1) It has a charge of +13 and is surrounded by a
total of 10 electrons.
(2) It has a charge of +13 and is surrounded by a
total of 13 electrons.
(3) It has a charge of –13 and is surrounded by a
total of 10 electrons.
(4) It has a charge of –13 and is surrounded by a
total of 13 electrons.
7 Which of these elements has the lowest melting
point?
(1) Li
(3) K
(2) Na
(4) Rb
8 Which list consists of elements that have the most
similar chemical properties?
(1) Mg, Al, and Si
(3) K, Al, and Ni
(2) Mg, Ca, and Ba
(4) K, Ca, and Ga
3 The atomic mass of an element is the weighted
average of the
(1) number of protons in the isotopes of that
element
(2) number of neutrons in the isotopes of that
element
(3) atomic numbers of the naturally occurring
isotopes of that element
(4) atomic masses of the naturally occurring
isotopes of that element
9 The correct chemical formula for iron(II) sulfide
is
(1) FeS
(3) FeSO4
(2) Fe2S3
(4) Fe2(SO4)3
10 Which list consists of types of chemical formulas?
(1) atoms, ions, molecules
(2) metals, nonmetals, metalloids
(3) empirical, molecular, structural
(4) synthesis, decomposition, neutralization
4 In which pair do the particles have approximately
the same mass?
(1) proton and electron
(2) proton and neutron
(3) neutron and electron
(4) neutron and beta particle
11 Which type of bonding is found in all molecular
substances?
(1) covalent bonding
(3) ionic bonding
(2) hydrogen bonding (4) metallic bonding
12 An aqueous solution of sodium chloride is best
classified as a
(1) homogeneous compound
(2) homogeneous mixture
(3) heterogeneous compound
(4) heterogeneous mixture
5 Two different samples decompose when heated.
Only one of the samples is soluble in water. Based
on this information, these two samples are
(1) both the same element
(2) two different elements
(3) both the same compound
(4) two different compounds
P.S./Chem.–Aug. ’05
[2]
19 Which formula represents an unsaturated hydrocarbon?
13 What is the total number of electrons shared in a
double covalent bond between two atoms?
(1) 1
(3) 8
(2) 2
(4) 4
H
14 Which formula represents a nonpolar molecule?
(3) CH4
(1) H2S
(2) HCl
(4) NH3
H
C
C
H
H
H
H
H
O
C
C
H
(3)
H
C
C
H
H
H
(1)
15 What occurs when an atom loses an electron?
(1) The atom’s radius decreases and the atom
becomes a negative ion.
(2) The atom’s radius decreases and the atom
becomes a positive ion.
(3) The atom’s radius increases and the atom
becomes a negative ion.
(4) The atom’s radius increases and the atom
becomes a positive ion.
H
H
H
H
C
C
H
H
(2)
CI
(4)
20 Given the formula:
16 Two samples of gold that have different temperatures are placed in contact with one another.
Heat will flow spontaneously from a sample of
gold at 60°C to a sample of gold that has a
temperature of
(1) 50°C
(3) 70°C
(2) 60°C
(4) 80°C
H
H
H
C
C
H
H
H
C
C
C
H
H
H
H
What is the IUPAC name of this compound?
(1) 2-pentene
(2) 2-pentyne
(3) 2-butene
(4) 2-butyne
21 Given the reaction system in a closed container at
equilibrium and at a temperature of 298 K:
17 Under which conditions of temperature and
pressure would helium behave most like an ideal
gas?
(1) 50 K and 20 kPa
(3) 750 K and 20 kPa
(2) 50 K and 600 kPa
(4) 750 K and 600 kPa
N2O4(g)
2NO2(g)
The measurable quantities of the gases at equilibrium must be
(1) decreasing
(2) increasing
18 A sample of oxygen gas is sealed in container X.
A sample of hydrogen gas is sealed in container Z.
Both samples have the same volume, temperature, and pressure. Which statement is true?
(1) Container X contains more gas molecules
than container Z.
(2) Container X contains fewer gas molecules
than container Z.
(3) Containers X and Z both contain the same
number of gas molecules.
(4) Containers X and Z both contain the same
mass of gas.
P.S./Chem.–Aug. ’05
H
(3) equal
(4) constant
22 Atoms of which element can bond with each other
to form ring and chain structures in compounds?
(1) C
(3) H
(2) Ca
(4) Na
23 In a voltaic cell, chemical energy is converted to
(1) electrical energy, spontaneously
(2) electrical energy, nonspontaneously
(3) nuclear energy, spontaneously
(4) nuclear energy, nonspontaneously
[3]
[OVER]
24 In each of the four beakers shown below, a 2.0-centimeter strip of magnesium ribbon reacts with
100 milliliters of HCl(aq) under the conditions shown.
0.1 M HCl
20°C
1.0 M HCl
20°C
0.1 M HCl
50°C
1.0 M HCl
50°C
Beaker A
Beaker B
Beaker C
Beaker D
In which beaker will the reaction occur at the fastest rate?
(1) A
(2) B
(3) C
(4) D
25 Which aqueous solution is the best conductor of
an electrical current?
(3) 0.1 M CH3OH
(1) 0.01 M CH3OH
(2) 0.01 M KOH
(4) 0.1 M KOH
29 Radioactive cobalt-60 is used in radiation therapy
treatment. Cobalt-60 undergoes beta decay. This
type of nuclear reaction is called
(1) natural transmutation
(2) artificial transmutation
(3) nuclear fusion
(4) nuclear fission
26 A hydrogen ion, H+, in aqueous solution may also
be written as
(3) H3O+
(1) H2O
(2) H2O2
(4) OH–
Note that question 30 has only three choices.
30 Given the balanced ionic equation:
27 One acid-base theory states that an acid is
(1) an electron donor
(3) an H+ donor
(2) a neutron donor
(4) an OH– donor
2Al(s) + 3Cu2+(aq) → 2Al3+(aq) + 3Cu(s)
Compared to the total charge of the reactants,
the total charge of the products is
28 Which isotope will spontaneously decay and emit
particles with a charge of +2?
(3) 198Au
(1) 53Fe
137
(2) Cs
(4) 220Fr
P.S./Chem.–Aug. ’05
(1) less
(2) greater
(3) the same
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
38 Given the balanced equation:
31 The percentage by mass of Br in the compound
AlBr3 is closest to
(1) 10.%
(3) 75%
(2) 25%
(4) 90.%
AgNO3(aq) + NaCl(aq) → NaNO3(aq) + AgCl(s)
This reaction is classified as
(1)
(2)
(3)
(4)
32 Which symbol represents a particle with a total of
10 electrons?
(1) N
(3) Al
3+
(2) N
(4) Al3+
39 A solution contains 35 grams of KNO3 dissolved
in 100 grams of water at 40°C. How much more
KNO3 would have to be added to make it a saturated solution?
(1) 29 g
(3) 12 g
(2) 24 g
(4) 4 g
33 Which electron configuration represents an atom
of aluminum in an excited state?
(1) 2-7-4
(3) 2-8-3
(2) 2-7-7
(4) 2-8-6
34 At STP, an element that is a brittle solid and a
poor conductor of heat and electricity could have
an atomic number of
(1) 12
(3) 16
(2) 13
(4) 17
40 Which diagram best represents a gas in a closed
container?
35 Based on Reference Table S, atoms of which of
these elements have the strongest attraction for
the electrons in a chemical bond?
(1) Al
(3) P
(2) Si
(4) S
36 A sample of a compound contains 65.4 grams of
zinc, 12.0 grams of carbon, and 48.0 grams of
oxygen. What is the mole ratio of zinc to carbon
to oxygen in this compound?
(1) 1:1:2
(3) 1:4:6
(2) 1:1:3
(4) 5:1:4
(1)
(3)
(2)
(4)
41 What is the total number of moles of NaCl(s)
needed to make 3.0 liters of a 2.0 M NaCl solution?
(1) 1.0 mol
(3) 6.0 mol
(2) 0.70 mol
(4) 8.0 mol
37 Which process would most effectively separate
two liquids with different molecular polarities?
(1) filtration
(3) distillation
(2) fermentation
(4) conductivity
P.S./Chem.–Aug. ’05
synthesis
decomposition
single replacement
double replacement
[5]
[OVER]
42 Which Lewis electron-dot diagram is correct for
a S2– ion?
S
2–
(1)
S
S
47 Given the incomplete equation representing an
organic addition reaction:
X(g) + Cl2(g) → XCl2(g)
2–
Which compound could be represented by X?
2–
(2)
S
(3) C3H8
(4) C4H10
(1) CH4
(2) C2H4
(3)
2–
48 Given the incomplete equation:
4Fe + 3O2 → 2X
(4)
Which compound is represented by X?
(3) Fe3O2
(4) Fe3O4
(1) FeO
(2) Fe2O3
43 A student wants to prepare a 1.0-liter solution of
a specific molarity. The student determines that
the mass of the solute needs to be 30. grams.
What is the proper procedure to follow?
(1) Add 30. g of solute to 1.0 L of solvent.
(2) Add 30. g of solute to 970. mL of solvent to
make 1.0 L of solution.
(3) Add 1000. g of solvent to 30. g of solute.
(4) Add enough solvent to 30. g of solute to make
1.0 L of solution.
49 How are HNO3(aq) and CH3COOH(aq) similar?
(1) They are Arrhenius acids and they turn blue
litmus red.
(2) They are Arrhenius acids and they turn red
litmus blue.
(3) They are Arrhenius bases and they turn blue
litmus red.
(4) They are Arrhenius bases and they turn red
litmus blue.
44 What is the total number of joules released when
a 5.00-gram sample of water changes from liquid
to solid at 0°C?
(1) 334 J
(3) 2260 J
(2) 1670 J
(4) 11 300 J
50 The chart below shows the spontaneous nuclear
decay of U-238 to Th-234 to Pa-234 to U-234.
U
238
Mass Number
45 Which set of procedures and observations indicates a chemical change?
(1) Ethanol is added to an empty beaker and the
ethanol eventually disappears.
(2) A solid is gently heated in a crucible and the
solid slowly turns to liquid.
(3) Large crystals are crushed with a mortar and
pestle and become powder.
(4) A cool, shiny metal is added to water in a
beaker and rapid bubbling occurs.
236
234
Th
Pa
U
232
230
88
89
90
91
92
Atomic Number
46 At STP, a sample of which element has the
highest entropy?
(1) Na(s)
(3) Br2()
(2) Hg()
(4) F2(g)
P.S./Chem.–Aug. ’05
What is the correct order of nuclear decay
modes for the change from U-238 to U-234?
(1)
(2)
(3)
(4)
[6]
β– decay, γ decay, β– decay
β– decay, β– decay, α decay
α decay, α decay, β– decay
α decay, β– decay, β– decay
Part B–2
Answer all questions in this part.
Directions (51–67): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
51 In the space in your answer booklet, show a correct numerical setup for calculating the
formula mass of glucose, C6H12O6. [1]
52 Write the empirical formula for the compound C6H12O6. [1]
Base your answers to questions 53 through 55 on the potential energy diagram below.
Potential Energy (kJ)
180
Without catalyst
160
With catalyst
140
120
100
80
60
40
20
0
Reaction Coordinate
53 What is the heat of reaction for the forward reaction? [1]
54 What is the activation energy for the forward reaction with the catalyst? [1]
55 Explain, in terms of the function of a catalyst, why the curves on the potential energy
diagram for the catalyzed and uncatalyzed reactions are different. [1]
Base your answers to questions 56 through 58 on the properties of propanone.
56 In the space in your answer booklet, draw the structural formula for propanone. [1]
57 Explain, in terms of molecular energy, why the vapor pressure of propanone increases
when its temperature increases. [1]
58 A liquid’s boiling point is the temperature at which its vapor pressure is equal to the
atmospheric pressure. Using Reference Table H, what is the boiling point of propanone
at an atmospheric pressure of 70 kPa? [1]
P.S./Chem.–Aug. ’05
[7]
[OVER]
Base your answers to questions 59 through 61 on the information below.
Two isotopes of potassium are K-37 and K-42.
59 What is the total number of neutrons in the nucleus of a K-37 atom? [1]
60 How many valence electrons are in an atom of K-42 in the ground state? [1]
61 Explain, in terms of subatomic particles, why K-37 and K-42 are isotopes of potassium. [1]
62 A sample of oxygen gas in one container has a volume of 20.0 milliliters at 297 K and
101.3 kPa. The entire sample is transferred to another container where the temperature
is 283 K and the pressure is 94.6 kPa. In the space in your answer booklet, show a correct
numerical setup for calculating the new volume of this sample of oxygen gas. [1]
63 In the space in your answer booklet, draw a Lewis electron-dot diagram for a molecule
of phosphorus trichloride, PCl3. [1]
Base your answers to questions 64 through 67 on the table below.
First Ionization Energy of Selected Elements
Element
Atomic
Number
First Ionization
Energy
(kJ/mol)
lithium
sodium
potassium
rubidium
cesium
3
11
19
37
55
520
496
419
403
376
64 On the grid in your answer booklet, mark an appropriate scale on the axis labeled
“First Ionization Energy (kJ/mol).” An appropriate scale is one that allows a trend to be
seen. [1]
65 On the same grid, plot the data from the table. Circle and connect the points. [1]
Example:
66 State the trend in first ionization energy for the elements in the table as the atomic
number increases. [1]
67 Explain, in terms of atomic structure, why cesium has a lower first ionization energy
than rubidium. [1]
P.S./Chem.–Aug. ’05
[8]
Part C
Answer all questions in this part.
Directions (68–85): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 68 through 70 on the information below.
The decomposition of sodium azide, NaN3(s), is used to inflate airbags. On impact, the
NaN3(s) is ignited by an electrical spark, producing N2(g) and Na(s). The N2(g) inflates the
airbag.
68 Balance the equation in your answer booklet, using the smallest whole-number
coefficients. [1]
69 What is the total number of moles present in a 52.0-gram sample of NaN3(s) (gramformula mass = 65.0 gram/mole)? [1]
70 An inflated airbag has a volume of 5.00 × 104 cm3 at STP. The density of N2(g) at STP
is 0.00125 g/cm3. What is the total number of grams of N2(g) in the airbag? [1]
Base your answers to questions 71 through 73 on the information below.
Element X is a solid metal that reacts with chlorine to form a water-soluble binary
compound.
71 State one physical property of element X that makes it a good material for making pots
and pans. [1]
72 Explain, in terms of particles, why an aqueous solution of the binary compound
conducts an electric current. [1]
73 The binary compound consists of element X and chlorine in a 1:2 molar ratio. What is
the oxidation number of element X in this compound? [1]
P.S./Chem.–Aug. ’05
[9]
[OVER]
Base your answers to questions 74 through 76 on the diagram and balanced equation below, which
represent the electrolysis of molten NaCl.
(+)
Battery
(–)
Switch
Positive
electrode
(anode)
Negative
electrode
(cathode)
Cl –
Na+
Molten NaCl (810°C)
2NaCl
Cl2 + 2Na
74 When the switch is closed, which electrode will attract the sodium ions? [1]
75 What is the purpose of the battery in this electrolytic cell? [1]
76 Write the balanced half-reaction for the reduction that occurs in this electrolytic cell. [1]
Base your answers to questions 77 through 79 on the information below.
In a titration, 3.00 M NaOH(aq) was added to an Erlenmeyer flask containing
25.00 milliliters of HCl(aq) and three drops of phenolphthalein until one drop of the
NaOH(aq) turned the solution a light-pink color. The following data were collected by a
student performing this titration.
Initial NaOH(aq) buret reading: 14.45 milliliters
Final NaOH(aq) buret reading: 32.66 milliliters
77 What is the total volume of NaOH(aq) that was used in this titration? [1]
78 In the space in your answer booklet, show a correct numerical setup for calculating the
molarity of the HCl(aq). [1]
79 Based on the data given, what is the correct number of significant figures that should
be shown in the molarity of the HCl(aq)? [1]
P.S./Chem.–Aug. ’05
[10]
Base your answers to questions 80 through 82 on the information below.
A student was studying the pH differences in samples from two Adirondack streams.
The student measured a pH of 4 in stream A and a pH of 6 in stream B.
80 Compare the hydronium ion concentration in stream A to the hydronium ion concentration in stream B. [1]
81 What is the color of bromthymol blue in the sample from stream A? [1]
82 Identify one compound that could be used to neutralize the sample from stream A. [1]
Base your answers to questions 83 through 85 on the information below.
The radioisotopes carbon-14 and nitrogen-16 are present in a living organism.
Carbon-14 is commonly used to date a once-living organism.
83 Complete the nuclear equation in your answer booklet for the decay of C-14. Include
both the atomic number and the mass number of the missing particle. [1]
84 Explain why N-16 is a poor choice for radioactive dating of a bone. [1]
85 A sample of wood is found to contain 18 as much C-14 as is present in the wood of a
living tree. What is the approximate age, in years, of this sample of wood? [1]
P.S./Chem.–Aug. ’05
[11]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Tuesday, August 16, 2005 — 12:30 to 3:30 p.m., only
ANSWER SHEET
■ Male ■ Female Grade
Student
..............................................
Sex:
...........
Teacher
..............................................
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Thursday, January 26, 2006 — 1:15 to 4:15 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
The use of any communications device is strictly prohibited when taking this
examination. If you use any communications device, no matter how briefly, your
examination will be invalidated and no score will be calculated for you.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
6 The element in Group 14, Period 3 on the
Periodic Table is classified as a
(1) metal
(3) metalloid
(2) noble gas
(4) nonmetal
1 Which two nuclides are isotopes of the same
element?
(1)
20 Na
11
(2)
39
19K
and 20
10Ne
and 40
20Ca
(3)
39 K
19
and 42
19K
(4)
14C
6
and 147N
7 Which trends are observed when the elements
in Period 3 on the Periodic Table are considered
in order of increasing atomic number?
(1) The atomic radius decreases, and the first
ionization energy generally increases.
(2) The atomic radius decreases, and the first
ionization energy generally decreases.
(3) The atomic radius increases, and the first
ionization energy generally increases.
(4) The atomic radius increases, and the first
ionization energy generally decreases.
2 An atom of oxygen is in an excited state. When
an electron in this atom moves from the third
shell to the second shell, energy is
(1) emitted by the nucleus
(2) emitted by the electron
(3) absorbed by the nucleus
(4) absorbed by the electron
3 The charge of a beryllium-9 nucleus is
(1) +13
(3) +5
(2) +9
(4) +4
8 What is the chemical formula for sodium
sulfate?
(1) Na2SO3
(3) NaSO3
(2) Na2SO4
(4) NaSO4
4 Which sequence represents a correct order of
historical developments leading to the modern
model of the atom?
(1) the atom is a hard sphere → most of the
atom is empty space → electrons exist in
orbitals outside the nucleus
(2) the atom is a hard sphere → electrons exist
in orbitals outside the nucleus → most of
the atom is empty space
(3) most of the atom is empty space → electrons
exist in orbitals outside the nucleus → the
atom is a hard sphere
(4) most of the atom is empty space → the atom
is a hard sphere → electrons exist in orbitals
outside the nucleus
9 Given the structural formula:
H H H H
HO C C C C OH
H H
What is the empirical formula of this compound?
(1) CH3O
(2) C2H5O
5 Which statement describes a chemical property
of oxygen?
(1) Oxygen has a melting point of 55 K.
(2) Oxygen can combine with a metal to produce a compound.
(3) Oxygen gas is slightly soluble in water.
(4) Oxygen gas can be compressed.
P.S./Chem.–Jan. ’06
H H
(3) C4H10O2
(4) C8H20O4
10 Which chemical equation is correctly balanced?
(1)
(2)
(3)
(4)
[2]
H2(g) + O2(g) → H2O(g)
N2(g) + H2(g) → NH3(g)
2NaCl(s) → Na(s) + Cl2(g)
2KCl(s) → 2K(s) + Cl2(g)
11 Compared to a calcium atom, the calcium ion
Ca2+ has
(1) more protons
(3) more electrons
(2) fewer protons
(4) fewer electrons
18 Given the balanced equation:
I2(s) + energy → I2(g)
As a sample of I2(s) sublimes to I2(g), the
entropy of the sample
(1) increases because the particles are less
randomly arranged
(2) increases because the particles are more
randomly arranged
(3) decreases because the particles are less
randomly arranged
(4) decreases because the particles are more
randomly arranged
12 Which type of bond is found in sodium bromide?
(1) covalent
(3) ionic
(2) hydrogen
(4) metallic
13 Which substance can not be decomposed by
ordinary chemical means?
(1) methane
(3) ethanol
(2) mercury
(4) ammonia
19 The multiple covalent bond in
1-butene is a
(1) double covalent bond that
electrons
(2) double covalent bond that
electrons
(3) triple covalent bond that
electrons
(4) triple covalent bond that
electrons
14 A mixture of crystals of salt and sugar is added to
water and stirred until all solids have dissolved.
Which statement best describes the resulting
mixture?
(1) The mixture is homogeneous and can be
separated by filtration.
(2) The mixture is homogeneous and cannot be
separated by filtration.
(3) The mixture is heterogeneous and can be
separated by filtration.
(4) The mixture is heterogeneous and cannot be
separated by filtration.
a molecule of
has 6 shared
has 4 shared
has 6 shared
has 4 shared
20 In an oxidation-reduction reaction, reduction is
defined as the
(1) loss of protons
(3) loss of electrons
(2) gain of protons
(4) gain of electrons
15 Under which conditions of temperature and
pressure would a sample of H2(g) behave most
like an ideal gas?
(1) 0°C and 100 kPa
(2) 0°C and 300 kPa
(3) 150°C and 100 kPa
(4) 150°C and 300 kPa
21 What is the oxidation number assigned to
manganese in KMnO4?
(1) +7
(3) +3
(2) +2
(4) +4
22 Which of the following aqueous solutions is the
best conductor of electricity?
(3) 0.10 M NaOH
(1) 0.10 M CH3OH
(2) 1.0 M CH3OH
(4) 1.0 M NaOH
16 In a chemical reaction, the difference between
the potential energy of the products and the
potential energy of the reactants is defined as the
(1) activation energy
(2) ionization energy
(3) heat of reaction
(4) heat of vaporization
23 One acid-base theory states that an acid is
–
+
(3) an H donor
(1) an H donor
–
+
(2) an H acceptor
(4) an H acceptor
17 Which substance is an Arrhenius base?
(1) KCl
(3) KOH
(2) CH3Cl
(4) CH3OH
P.S./Chem.–Jan. ’06
[3]
[OVER]
28 Which structural formula is correct for
2-methyl-3-pentanol?
24 Positrons are spontaneously emitted from the
nuclei of
(1) potassium-37
(3) nitrogen-16
(2) radium-226
(4) thorium-232
H
H
25 The amount of energy released from a fission
reaction is much greater than the energy
released from a chemical reaction because in a
fission reaction
(1) mass is converted into energy
(2) energy is converted into mass
(3) ionic bonds are broken
(4) covalent bonds are broken
H
H
H
C
C
C
H
H
H
H
H
C
C
C
H
H
H
H
H
H
H
C
H
H
OH
C
C
C
C
H
H
H
H
H C
H
OH
H
(1)
(3)
H
26 Which Lewis electron-dot diagram is correct for
CO2?
H
O
C O
(1)
O
C
O
O C O
(2)
(4)
C
C
H
H
H
H
H
H
C
C
C
H
H
(2)
H
H
H
H H
H
C
C
C
C
H
H
H
OH
H C
H
H
(4)
Note that questions 29 and 30 have only
three choices.
29 When an atom becomes a positive ion, the radius
of the atom
(1) decreases
(2) increases
(3) remains the same
27 Types of nuclear reactions include fission,
fusion, and
(1) single replacement
(2) neutralization
(3) oxidation-reduction
(4) transmutation
P.S./Chem.–Jan. ’06
C
OH
(3)
O
C O
H
H
30 Compared to the freezing point of 1.0 M KCl(aq)
at standard pressure, the freezing point of 1.0 M
CaCl2(aq) at standard pressure is
(1) lower
(2) higher
(3) the same
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
34 The atomic mass of element A is 63.6 atomic
mass units. The only naturally occurring isotopes of element A are A-63 and A-65. The percent abundances in a naturally occurring sample
of element A are closest to
(1) 31% A-63 and 69% A-65
(2) 50% A-63 and 50% A-65
(3) 69% A-63 and 31% A-65
(4) 100% A-63 and 0% A-65
31 Which electron configuration represents the electrons in an atom of chlorine in an excited state?
(1) 2-7-7
(3) 2-8-7
(2) 2-7-8
(4) 2-8-8
32 Given the particle diagram representing four
molecules of a substance:
35 Elements Q, X, and Z are in the same group on
the Periodic Table and are listed in order of
increasing atomic number. The melting point of
element Q is –219°C and the melting point of
element Z is –7°C. Which temperature is closest
to the melting point of element X?
(1) –7°C
(3) –219°C
(2) –101°C
(4) –226°C
Which particle diagram best represents this same
substance after a physical change has taken
place?
36 Given the balanced equation:
2C + 3H2 → C2H6
(1)
What is the total number of moles of C that
must completely react to produce 2.0 moles of
C2H6?
(3)
(1) 1.0 mol
(2) 2.0 mol
(3) 3.0 mol
(4) 4.0 mol
37 Given the balanced equation:
2KClO3 → 2KCl + 3O2
Which type of reaction is represented by this
equation?
(2)
(4)
(1)
(2)
(3)
(4)
33 What is the percent composition by mass of
nitrogen in NH4NO3 (gram-formula mass = 80.0
grams/mole)?
(1) 17.5%
(3) 52.5%
(2) 35.0%
(4) 60.0%
P.S./Chem.–Jan. ’06
[5]
synthesis
decomposition
single replacement
double replacement
[OVER]
38 A solid substance was tested in the laboratory.
The test results are listed below.
• dissolves in water
• is an electrolyte
• melts at a high temperature
43 Given the potential energy diagram for a chemical reaction:
60.
50.
(1) Cu
(2) CuBr2
Potential Energy (kJ)
Based on these results, the solid substance could
be
(3) C
(4) C6H12O6
39 If 0.025 gram of Pb(NO3)2 is dissolved in
100. grams of H2O, what is the concentration of
the resulting solution, in parts per million?
(3) 250 ppm
(1) 2.5 × 10–4 ppm
(2) 2.5 ppm
(4) 4.0 × 103 ppm
40.
30.
20.
10.
0
Reaction Coordinate
40 Given the balanced equation:
4Fe(s) + 3O2(g) → 2Fe2O3(s) + 1640 kJ
Which statement correctly describes the energy
changes that occur in the forward reaction?
Which phrase best describes this reaction?
(1)
(2)
(3)
(4)
endothermic with ∆H = +1640 kJ
endothermic with ∆H = –1640 kJ
exothermic with ∆H = +1640 kJ
exothermic with ∆H = –1640 kJ
(1) The activation energy is
reaction is endothermic.
(2) The activation energy is
reaction is exothermic.
(3) The activation energy is
reaction is endothermic.
(4) The activation energy is
reaction is exothermic.
41 A student adds solid KCl to water in a flask. The
flask is sealed with a stopper and thoroughly
shaken until no more solid KCl dissolves. Some
solid KCl is still visible in the flask. The solution
in the flask is
(1) saturated and is at equilibrium with the solid
KCl
(2) saturated and is not at equilibrium with the
solid KCl
(3) unsaturated and is at equilibrium with the
solid KCl
(4) unsaturated and is not at equilibrium with
the solid KCl
H O
H C C
H
50. kJ and the
50. kJ and the
H
N
H
This compound is classified as an
(1) amide
(2) amine
(3) aldehyde
(4) alcohol
45 Which formula represents an unsaturated
hydrocarbon?
(1) CH2CHCl
(3) CH3CH2CH3
(2) CH3CH2Cl
(4) CH3CHCH2
2C2H6 + 7O2 → 4CO2 + 6 ____
What is the formula of the missing product?
P.S./Chem.–Jan. ’06
10. kJ and the
44 Given the structural formula:
42 Given the incomplete equation for the combustion of ethane:
(1) CH3OH
(2) HCOOH
10. kJ and the
(3) H2O
(4) H2O2
[6]
49 Given the nuclear equation:
46 Given the balanced equation for an organic
reaction:
1H
1
C2H2 + 2Cl2 → C2H2Cl4
+ X → 63Li + 42He
This reaction is best classified as
The particle represented by X is
(1) addition
(2) esterification
(1) 94Li
(3)
(2) 94Be
(4)
(3) fermentation
(4) substitution
47 Which indicator is yellow in a solution with a
pH of 9.8?
(1) methyl orange
(3) bromcresol green
(2) bromthymol blue
(4) thymol blue
10 Be
5
10 C
6
50 The decay of which radioisotope can be used to
estimate the age of the fossilized remains of an
insect?
(1) Rn-222
(3) Co-60
(2) I-131
(4) C-14
48 How many milliliters of 0.100 M NaOH(aq)
would be needed to completely neutralize
50.0 milliliters of 0.300 M HCl(aq)?
(1) 16.7 mL
(3) 150. mL
(2) 50.0 mL
(4) 300. mL
P.S./Chem.–Jan. ’06
[7]
[OVER]
Part B–2
Answer all questions in this part.
Directions (51–67): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
51 What is the total number of neutrons in an atom of aluminum-27?
[1]
52 Explain, in terms of atomic structure, why the atomic radius of iodine is greater than
the atomic radius of fluorine. [1]
53 In the space in your answer booklet, draw a Lewis electron-dot diagram of a selenium
atom in the ground state. [1]
54 Explain, in terms of atomic structure, why liquid mercury is a good electrical conductor. [1]
55 Given the structural formula of pentane:
H H H H H
H C C C C C H
H H H H H
In the space in your answer booklet, draw a structural formula for an isomer of
pentane. [1]
56 Based on Reference Table N, what is the fraction of a sample of potassium-42 that will
remain unchanged after 62.0 hours? [1]
57 What is the total number of moles in 80.0 grams of C2H5Cl (gram-formula mass = 64.5
grams/mole)? [1]
58 What is the total amount of heat energy, in joules, absorbed by 25.0 grams of water
when the temperature of the water increases from 24.0°C to 36.0°C? [1]
Base your answers to questions 59 and 60 on the information and balanced equation below.
Given the equation for a reaction at equilibrium:
2SO2(g) + O2(g)
2SO3(g) + energy
59 Explain, in terms of LeChatelier’s principle, why the concentration of SO2(g) increases
when the temperature is increased. [1]
60 Explain, in terms of collisions between molecules, why increasing the concentration of
O2(g) produces a decrease in the concentration of SO2(g). [1]
P.S./Chem.–Jan. ’06
[8]
Base your answers to questions 61 through 65 on the table below.
Physical Properties of Four Gases
Name of Gas
Molecular Structure
Boiling Point (K) at 1 Atm
Density (g/L) at STP
hydrogen
hydrogen
chloride
hydrogen
bromide
hydrogen
iodide
H–H
H–Cl
H–Br
H–I
20.
188
207
237
0.0899
1.64
?
5.66
61 The volume of 1.00 mole of hydrogen bromide at STP is 22.4 liters. The gram-formula
mass of hydrogen bromide is 80.9 grams per mole. What is the density of hydrogen
bromide at STP? [1]
62 The density of hydrogen at STP is 0.0899 gram per liter. Express this density to two
significant figures. [1]
63 Explain, in terms of electronegativity difference, why the bond in H–Cl is more polar
than the bond in H–I. [1]
64 Explain, in terms of intermolecular forces, why hydrogen has a lower boiling point than
hydrogen bromide. [1]
65 Explain, in terms of molecular polarity, why hydrogen chloride is more soluble than
hydrogen in water under the same conditions of temperature and pressure. [1]
Base your answers to questions 66 and 67 on the graph below, which represents the cooling of a substance
starting at a temperature above its boiling point.
200
Temperature (°C)
180
160
A
140
120
100
C
B
80
60
40
E
D
20
F
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Time (min)
66 What is the melting point of this substance?
[1]
67 Which segment of the graph represents the gas phase, only?
P.S./Chem.–Jan. ’06
[9]
[1]
[OVER]
Part C
Answer all questions in this part.
Directions (68–85): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 68 through 70 on the information and table below.
A student conducts an experiment to determine how the temperature of water affects
the rate at which an antacid tablet dissolves in the water. The student has three antacid
tablets of the same size and composition. The student drops one tablet into each of three
beakers containing 200. milliliters of water at different temperatures and measures the
time it takes for each tablet to completely dissolve. The results are shown in the table
below.
Dissolving Data for Three Antacid Tablets
Beaker
Original
Temperature
of Water (°C)
Time for Tablet
to Dissolve
(s)
1
20.
40.
2
30.
25
3
40.
10.
68 Describe the effect of water temperature on the rate of dissolving.
[1]
69 Explain, in terms of collision theory, how water temperature influences the rate of
dissolving. [1]
70 What change, other than temperature, would affect the rate of dissolving?
P.S./Chem.–Jan. ’06
[10]
[1]
Base your answers to questions 71 through 74 on the passage below.
Acid rain lowers the pH in ponds and lakes and over time can cause the death of some
aquatic life. Acid rain is caused in large part by the burning of fossil fuels in power plants and
by gasoline-powered vehicles. The acids commonly associated with acid rain are sulfurous
acid, sulfuric acid, and nitric acid.
In general, fish can tolerate a pH range between 5 and 9. However, even small changes in
pH can significantly affect the solubility and toxicity of common pollutants. Increased
concentrations of these pollutants can adversely affect the behavior and normal life processes
of fish and cause deformity, lower egg production, and less egg hatching.
71 Acid rain caused the pH of a body of water to decrease. Explain this pH decrease in
terms of the change in concentration of hydronium ions. [1]
72 Write the chemical formula of a negative polyatomic ion present in an aqueous nitric
acid solution. [1]
73 Using information in the passage, describe one effect of acid rain on future generations
of fish species in ponds and lakes. [1]
74 Sulfur dioxide, SO2, is one of the gases that reacts with water to produce acid rain.
According to Reference Table G, describe how the solubility of sulfur dioxide in water
is affected by an increase in water temperature. [1]
Base your answers to questions 75 through 77 on the information below.
A student is instructed to make 0.250 liter of a 0.200 M aqueous solution of Ca(NO3)2.
75 What is the gram-formula mass of Ca(NO3)2?
[1]
76 In the space in your answer booklet, show a correct numerical setup for calculating the
total number of moles of Ca(NO3)2 needed to make 0.250 liter of the 0.200 M calcium
nitrate solution. [1]
77 In order to prepare the described solution in the laboratory, two quantities must be
measured accurately. One of these quantities is the volume of the solution. What other
quantity must be measured to prepare this solution? [1]
P.S./Chem.–Jan. ’06
[11]
[OVER]
Base your answers to questions 78 through 80 on the data in Reference Table S.
78 On the data table in your answer booklet, record the boiling points for He, Ne, Ar, Kr,
and Xe. [1]
79 On the grid in your answer booklet, plot the boiling point versus the atomic number for
He, Ne, Ar, Kr, and Xe. Circle and connect the points. [1]
Example:
80 Based on your graph, describe the trend in the boiling points of these elements as the
atomic number increases. [1]
Base your answers to questions 81 and 82 on the information below.
A lightbulb contains argon gas at a temperature of 295 K and at a pressure of 75 kilopascals. The lightbulb is switched on, and after 30 minutes its temperature is 418 K.
81 In the space in your answer booklet, show a correct numerical setup for calculating the
pressure of the gas inside the lightbulb at 418 K. Assume the volume of the lightbulb
remains constant. [1]
82 What Celsius temperature is equal to 418 K?
[1]
83 Because tap water is slightly acidic, water pipes made of iron corrode over time, as
shown by the balanced ionic equation below:
2Fe + 6H+ → 2Fe3+ + 3H2
Explain, in terms of chemical reactivity, why copper pipes are less likely to corrode than
iron pipes. [1]
P.S./Chem.–Jan. ’06
[12]
Base your answers to questions 84 and 85 on the information and diagram below.
The apparatus shown in the diagram consists of two inert platinum electrodes
immersed in water. A small amount of an electrolyte, H2SO4, must be added to the water
for the reaction to take place. The electrodes are connected to a source that supplies electricity.
O (g)
H (g)
2
2
H O( ) + H SO (aq)
2
Platinum electrode
2
4
Platinum electrode
(+)
(–)
Battery
84 What type of electrochemical cell is shown?
[1]
85 What particles are provided by the electrolyte that allow an electric current to flow? [1]
P.S./Chem.–Jan. ’06
[13]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Thursday, January 26, 2006 — 1:15 to 4:15 p.m., only
ANSWER SHEET
■ Male ■ Female Grade . . . . . . . . . . . .
Student
..............................................
Sex:
Teacher
..............................................
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Wednesday, June 21, 2006 — 1:15 to 4:15 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
The use of any communications device is strictly prohibited when taking this
examination. If you use any communications device, no matter how briefly, your
examination will be invalidated and no score will be calculated for you.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
7 Given the balanced equation representing a
reaction:
1 Which notation represents an atom of sodium
with an atomic number of 11 and a mass number
of 24?
(1) 24
(3) 13
11Na
11Na
(2)
11Na
24
(4)
F2(g) + H2(g) → 2HF(g)
What is the mole ratio of H2(g) to HF(g) in this
reaction?
35Na
11
(1) 1:1
(2) 1:2
2 Which element has chemical properties that are
most similar to those of calcium?
(1) Co
(3) N
(2) K
(4) Sr
8 Which list includes three types of chemical
reactions?
(1) condensation, double replacement, and
sublimation
(2) condensation, solidification, and synthesis
(3) decomposition, double replacement, and
synthesis
(4) decomposition, solidification, and sublimation
3 Which element is malleable and can conduct
electricity in the solid phase?
(1) iodine
(3) sulfur
(2) phosphorus
(4) tin
4 Atoms of different isotopes of the same element
differ in their total number of
(1) electrons
(3) protons
(2) neutrons
(4) valence electrons
5 Which statement correctly describes
of oxygen, O2 and O3?
(1) They have identical molecular
and identical properties.
(2) They have identical molecular
and different properties.
(3) They have different molecular
and identical properties.
(4) They have different molecular
and different properties.
9 Which type of bond results when one or more
valence electrons are transferred from one atom
to another?
(1) a hydrogen bond
(2) an ionic bond
(3) a nonpolar covalent bond
(4) a polar covalent bond
two forms
structures
10 What is the total number of electrons shared in
the bonds between the two carbon atoms in a
molecule of H C C H ?
(1) 6
(3) 3
(2) 2
(4) 8
structures
structures
structures
11 Which formula represents a nonpolar molecule?
(1) CH4
(3) H2O
(2) HCl
(4) NH3
6 What is the IUPAC name for the compound
FeS?
(1) iron(II) sulfate
(3) iron(II) sulfide
(2) iron(III) sulfate
(4) iron(III) sulfide
P.S./Chem.–June ’06
(3) 2:1
(4) 2:3
[2]
18 Which expression represents the ΔH for a
chemical reaction in terms of the potential energy,
PE, of its products and reactants?
(1) PE of products + PE of reactants
(2) PE of products – PE of reactants
(3) PE of products × PE of reactants
(4) PE of products ÷ PE of reactants
12 Which changes occur as a cadmium atom, Cd,
becomes a cadmium ion, Cd2+?
(1) The Cd atom gains two electrons and its
radius decreases.
(2) The Cd atom gains two electrons and its
radius increases.
(3) The Cd atom loses two electrons and its
radius decreases.
(4) The Cd atom loses two electrons and its
radius increases.
19 Which balanced equation represents an
endothermic reaction?
(1) C(s) + O2(g) → CO2(g)
(2) CH4(g) + 2O2(g) → CO2(g) + 2H2O(ᐉ)
(3) N2(g) + 3H2(g) → 2NH3(g)
(4) N2(g) + O2(g) → 2NO(g)
13 Which element has atoms with the greatest
attraction for electrons in a chemical bond?
(1) beryllium
(3) lithium
(2) fluorine
(4) oxygen
20 Which formula represents propyne?
(3) C5H8
(1) C3H4
(2) C3H6
(4) C5H10
14 Two substances, A and Z, are to be identified.
Substance A can not be broken down by a
chemical change. Substance Z can be broken
down by a chemical change. What can be concluded about these substances?
(1) Both substances are elements.
(2) Both substances are compounds.
(3) Substance A is an element and substance Z
is a compound.
(4) Substance A is a compound and substance Z
is an element.
21 Which factors must be equal in a reversible
chemical reaction at equilibrium?
(1) the activation energies of the forward and
reverse reactions
(2) the rates of the forward and reverse reactions
(3) the concentrations of the reactants and
products
(4) the potential energies of the reactants and
products
15 Which ion, when combined with chloride
ions, Cl–, forms an insoluble substance in water?
(3) Pb2+
(1) Fe2+
2+
(2) Mg
(4) Zn2+
22 The compounds CH3OCH3 and CH3CH2OH are
isomers of each other. These two compounds
must have the same
(1) density
(3) melting point
(2) reactivity
(4) molecular formula
16 Molarity is defined as the
(1) moles of solute per kilogram of solvent
(2) moles of solute per liter of solution
(3) mass of a solution
(4) volume of a solvent
23 Which balanced equation represents a redox
reaction?
(1) AgNO3 + NaCl → AgCl + NaNO3
(2) BaCl2 + K2CO3 → BaCO3 + 2KCl
(3) CuO + CO → Cu + CO2
(4) HCl + KOH → KCl + H2O
17 Which formula represents a hydrocarbon?
(1) CH3CH2CH2CHO
(2) CH3CH2CH2CH3
(3) CH3CH2CH2COOH
(4) CH3CH2COOCH3
P.S./Chem.–June ’06
[3]
[OVER]
24 Which process occurs at the anode in an
electrochemical cell?
(1) the loss of protons
(2) the loss of electrons
(3) the gain of protons
(4) the gain of electrons
28 Which equation represents the radioactive decay
of 226
88Ra?
(1)
(2)
(3)
(4)
25 Which substance is an electrolyte?
(1) CH3OH
(3) H2O
(2) C6H12O6
(4) KOH
4
→ 222
86Rn + 2He
0
→ 226
89Ac +–1e
0
→ 226
87Fr ++1e
1
→ 225
88Ra + 0n
29 Which type of reaction converts one element to
another element?
(1) neutralization
(3) substitution
(2) polymerization
(4) transmutation
26 Which ion is the only negative ion present in an
aqueous solution of an Arrhenius base?
(1) hydride ion
(3) hydronium ion
(2) hydrogen ion
(4) hydroxide ion
30 Which nuclear emission has the greatest mass?
(1) α
(3) ␤–
(2) γ
(4) ␤+
27 According to Reference Table N, which pair of
isotopes spontaneously decays?
(1) C-12 and N-14
(3) C-14 and N-14
(2) C-12 and N-16
(4) C-14 and N-16
P.S./Chem.–June ’06
226Ra
88
226Ra
88
226Ra
88
226Ra
88
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
36 A metal, M, forms an oxide compound with the
general formula M2O. In which group on the
Periodic Table could metal M be found?
(1) Group 1
(3) Group 16
(2) Group 2
(4) Group 17
31 Which trends are observed as each of the
elements within Group 15 on the Periodic Table
is considered in order from top to bottom?
(1) Their metallic properties decrease and their
atomic radii decrease.
(2) Their metallic properties decrease and their
atomic radii increase.
(3) Their metallic properties increase and their
atomic radii decrease.
(4) Their metallic properties increase and their
atomic radii increase.
37 Given the key:
Key
= Atom of oxygen
= Atom of carbon
32 What is the total number of electrons in a
S2– ion?
(1) 10
(3) 16
(2) 14
(4) 18
Which particle diagram represents a sample
containing the compound CO(g)?
33 A substance has an empirical formula of CH2
and a molar mass of 56 grams per mole. The
molecular formula for this compound is
(3) C4H8
(1) CH2
(2) C4H6
(4) C8H4
(1)
(3)
(2)
(4)
34 Compared to an atom of phosphorus-31, an
atom of sulfur-32 contains
(1) one less neutron
(3) one more neutron
(2) one less proton
(4) one more proton
35 In which compound is the percent composition
by mass of chlorine equal to 42%?
(1) HClO (gram-formula mass = 52 g/mol)
(2) HClO2 (gram-formula mass = 68 g/mol)
(3) HClO3 (gram-formula mass = 84 g/mol)
(4) HClO4 (gram-formula mass = 100. g/mol)
P.S./Chem.–June ’06
38 At standard pressure, which element has a
melting point higher than standard temperature?
(3) Fe
(1) F2
(2) Br2
(4) Hg
[5]
[OVER]
45 Given the formula:
39 Which Lewis electron-dot diagram represents
chloroethene?
H H
H C C Cl
H H
H C C Cl
H H
(1)
(3)
H H
H C C Cl
H
H C Cl
H
(2)
H H H O
H C C C C
H
N
H
H H H
This compound is classified as
(1) an aldehyde
(2) an amide
(3) an amine
(4) a ketone
46 Given the balanced equation with an unknown
compound represented by X:
C6H12O6(aq)
(4)
enzyme
2X + 2CO2(g)
Which compound is represented by X?
40 A saturated solution of NaNO3 is prepared at
60.°C using 100. grams of water. As this solution
is cooled to 10.°C, NaNO3 precipitates (settles)
out of the solution. The resulting solution is
saturated. Approximately how many grams of
NaNO3 settled out of the original solution?
(1) 46 g
(3) 85 g
(2) 61 g
(4) 126 g
(1)
(2)
(3)
(4)
CH3OH(aq)
CH2(OH)4(aq)
CH3CH2OH(aq)
CH2OHCH2OH(aq)
47 Which reactants form the salt CaSO4(s) in a
neutralization reaction?
(1)
(2)
(3)
(4)
41 Which kelvin temperature is equivalent to –24°C?
(1) 226 K
(3) 273 K
(2) 249 K
(4) 297 K
H2S(g) and Ca(ClO4)2(s)
H2SO3(aq) and Ca(NO3)2(aq)
H2SO4(aq) and Ca(OH)2(aq)
SO2(g) and CaO(s)
42 Which substance has the lowest vapor pressure
at 75°C?
(1) water
(3) propanone
(2) ethanoic acid
(4) ethanol
48 A student tested a 0.1 M aqueous solution and
made the following observations:
• conducts electricity
• turns blue litmus to red
• reacts with Zn(s) to produce gas bubbles
43 What is the IUPAC name for the compound
that has the condensed structural formula
CH3CH2CH2CHO?
(1) butanal
(3) propanal
(2) butanol
(4) propanol
Which compound could be the solute in this
solution?
(1) CH3OH
(2) LiBr
49 What is the half-life of sodium-25 if 1.00 gram of
a 16.00-gram sample of sodium-25 remains
unchanged after 237 seconds?
(1) 47.4 s
(3) 79.0 s
(2) 59.3 s
(4) 118 s
44 What volume of 0.500 M HNO3(aq) must completely react to neutralize 100.0 milliliters of
0.100 M KOH(aq)?
(1) 10.0 mL
(3) 50.0 mL
(2) 20.0 mL
(4) 500. mL
P.S./Chem.–June ’06
(3) HBr
(4) LiOH
[6]
50 Given the table below that shows students’ examples of proposed models of the atom:
Proposed Models of the Atom
Model
Location of Protons
Location of Electrons
A
in the nucleus
specific shells
B
in the nucleus
regions of most probable
location
C
dispersed throughout the atom
specific shells
D
dispersed throughout the atom
regions of most probable
location
Which model correctly describes the locations of protons and electrons in the
wave-mechanical model of the atom?
(1) A
(3) C
(2) B
(4) D
P.S./Chem.–June ’06
[7]
[OVER]
Part B–2
Answer all questions in this part.
Directions (51–66): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 51 and 52 on the balanced equation below.
Fe(s) + 2HNO3(aq) → Fe(NO3)2(aq) + H2(g)
51 What is the total number of oxygen atoms represented in the formula of the iron
compound produced? [1]
52 Explain, using information from Reference Table J, why this reaction is spontaneous. [1]
Base your answers to questions 53 and 54 on the information below.
An atom has an atomic number of 9, a mass number of 19, and an electron configuration of 2–6–1.
53 What is the total number of neutrons in this atom? [1]
54 Explain why the number of electrons in the second and third shells shows that this atom
is in an excited state. [1]
55 To which homologous series does CH3CH2CH2CH3 belong? [1]
56 What is the mass of 4.76 moles of Na3PO4 (gram-formula mass = 164 grams/mole)? [1]
Base your answers to questions 57 and 58 on the information below.
Given the balanced equation for dissolving NH4Cl(s) in water:
NH4Cl(s)
H2O
+
NH4 (aq) + Cl–(aq)
57 A student is holding a test tube containing 5.0 milliliters of water. When a sample of
NH4Cl(s) is placed in the test tube, the test tube feels colder to the student’s hand.
Describe the direction of heat flow between the test tube and the hand. [1]
58 Using the key in your answer booklet, draw at least two water molecules in the box,
showing the correct orientation of each water molecule when it is near the Cl– ion in
the aqueous solution. [1]
P.S./Chem.–June ’06
[8]
Base your answers to questions 59 and 60 on the information below.
Given the reaction at equilibrium:
2NO2(g)
N2O4(g) + 55.3 kJ
59 Explain, in terms of energy, why the forward reaction is exothermic. [1]
60 Explain, in terms of Le Chatelier’s principle, why the equilibrium shifts to the right to relieve
the stress when the pressure on the system is increased at constant temperature. [1]
Base your answers to questions 61 through 63 on the information below.
Given the balanced equation for an organic reaction between butane and chlorine that
takes place at 300.°C and 101.3 kilopascals:
C4H10 + Cl2 → C4H9Cl + HCl
61 Identify the type of organic reaction shown. [1]
62 In the space in your answer booklet, draw a structural formula for the organic
product. [1]
63 Explain, in terms of collision theory, why the rate of the reaction would decrease if the
temperature of the reaction mixture was lowered to 200.°C with pressure remaining
unchanged. [1]
Base your answers to questions 64 through 66 on the information below.
Ethanol, C2H5OH, is a volatile and flammable liquid with a distinct odor at room
temperature. Ethanol is soluble in water. The boiling point of ethanol is 78.2°C at
1 atmosphere. Ethanol can be used as a fuel to produce heat energy, as shown by the
balanced equation below.
C2H5OH(ᐉ) + 3O2(g) → 2CO2(g) + 3H2O(ᐉ) + 1367 kJ
64 At 1 atmosphere, compare the boiling point of pure ethanol to the boiling point of a
solution in which a nonvolatile substance is dissolved in ethanol. [1]
65 Determine the total amount of heat produced by the complete combustion of
2.00 moles of ethanol. [1]
66 Identify one physical property of ethanol, stated in the passage, that can be explained in
terms of chemical bonds and intermolecular forces. [1]
P.S./Chem.–June ’06
[9]
[OVER]
Part C
Answer all questions in this part.
Directions (67–84): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 67 and 68 on the information below.
The graph shows the relationship between the solubility of a sequence of primary
alcohols in water and the total number of carbon atoms in a molecule of the corresponding
alcohol at the same temperature and pressure. A primary alcohol has the – OH group located
on an end carbon of the hydrocarbon chain.
Solubility Versus Total Number
of Carbon Atoms
Solubility (g/110. g of water)
9
8
7
6
5
4
3
2
1
0
3
4
5
6
7
8
9
10 11
Total Number of Carbon Atoms
Adapted from Chemistry, Collins
Educational Publishing, pp. 227-231
67 Describe the relationship between the solubility of a primary alcohol in water and the
total number of carbon atoms in the primary alcohol. [1]
68 Determine the total mass of 1-pentanol that will dissolve in 110. grams of water to
produce a saturated solution. [1]
P.S./Chem.–June ’06
[10]
Base your answers to questions 69 and 70 on the information below.
Air bags are an important safety feature in modern automobiles. An air bag is inflated
in milliseconds by the explosive decomposition of NaN3(s). The decomposition reaction
produces N2(g), as well as Na(s), according to the unbalanced equation below.
NaN3(s) → Na(s) + N2(g)
69 Balance the equation in your answer booklet for the decomposition of NaN3, using the
smallest whole-number coefficients. [1]
70 When the air bag inflates, the nitrogen gas is at a pressure of 1.30 atmospheres, a
temperature of 301 K, and has a volume of 40.0 liters. In the space in your answer
booklet, calculate the volume of the nitrogen gas at STP. Your response must include
both a correct numerical setup and the calculated volume. [2]
Base your answers to questions 71 and 72 on the information below.
A thiol is very similar to an alcohol, but a thiol has a sulfur atom instead of an oxygen
atom in the functional group. One of the compounds in a skunk’s spray is 2-butene-1-thiol.
The formula of this compound is shown below.
H H
H
H C C C C
SH
H
H H
71 Explain, in terms of composition, why this compound is a thiol. [1]
72 Explain, in terms of electron configuration, why oxygen atoms and sulfur atoms form
compounds with similar molecular structures. [1]
P.S./Chem.–June ’06
[11]
[OVER]
Base your answers to questions 73 through 75 on the graph below. The graph shows the relationship
between pH value and hydronium ion concentration for common aqueous solutions and mixtures.
pH Versus Hydronium Ion Concentration
14
Bleach
12
Aqueous ammonia
Milk of magnesia
10.
Seawater
8
pH
Blood
Milk
6
4
2
Tomato juice
Lemon juice
Stomach fluids (gastric juice)
0
100
10–2
10–4
10–6
10–8
10–10
10–12
10–14
Hydronium Ion Concentration (M)
73 What is the hydronium ion concentration of tomato juice? [1]
74 What color is thymol blue when added to milk of magnesia? [1]
75 According to this graph, which mixture is approximately 100 times more acidic than
milk of magnesia? [1]
P.S./Chem.–June ’06
[12]
Base your answers to questions 76 and 77 on the information below.
Archimedes (287–212 BC), a Greek inventor and mathematician, made several
discoveries important to science today. According to a legend, Hiero, the king of Syracuse,
commanded Archimedes to find out if the royal crown was made of gold, only. The king
suspected that the crown consisted of a mixture of gold, tin, and copper.
Archimedes measured the mass of the crown and the total amount of water displaced
by the crown when it was completely submerged. He repeated the procedure using
individual samples, one of gold, one of tin, and one of copper. Archimedes was able to
determine that the crown was not made entirely of gold without damaging it.
76 Identify one physical property that Archimedes used in his comparison of the metal
samples. [1]
77 Determine the volume of a 75-gram sample of gold at STP. [1]
Base your answers to questions 78 through 81 on the information below.
Aluminum is one of the most abundant metals in Earth’s crust. The aluminum
compound found in bauxite ore is Al2O3. Over one hundred years ago, it was difficult and
expensive to isolate aluminum from bauxite ore. In 1886, a brother and sister team, Charles
and Julia Hall, found that molten (melted) cryolite, Na3AlF6, would dissolve bauxite ore.
Electrolysis of the resulting mixture caused the aluminum ions in the Al2O3 to be reduced
to molten aluminum metal. This less expensive process is known as the Hall process.
78 Write the oxidation state for each of the elements in cryolite. [1]
79 Write the balanced half-reaction equation for the reduction of Al3+ to Al. [1]
80 Explain, in terms of ions, why molten cryolite conducts electricity. [1]
81 Explain, in terms of electrical energy, how the operation of a voltaic cell differs from the
operation of an electrolytic cell used in the Hall process. Include both the voltaic cell and
the electrolytic cell in your answer. [1]
P.S./Chem.–June ’06
[13]
[OVER]
Base your answers to questions 82 through 84 on the information below.
A glass tube is filled with hydrogen gas at low pressure. An electric current is passed
through the gas, causing it to emit light. This light is passed through a prism to separate the
light into the bright, colored lines of hydrogen’s visible spectrum. Each colored line
corresponds to a particular wavelength of light. One of hydrogen’s spectral lines is red light
with a wavelength of 656 nanometers.
Tubes filled with other gases produce different bright-line spectra that are characteristic
of each kind of gas. These spectra have been observed and recorded.
82 Explain, in terms of electron energy states and energy changes, how hydrogen’s brightline spectrum is produced. [1]
83 Explain how the elements present on the surface of a star can be identified using brightline spectra. [1]
84 A student measured the wavelength of hydrogen’s visible red spectral line to be
647 nanometers. In the space in your answer booklet, show a correct numerical setup
for calculating the student’s percent error. [1]
P.S./Chem.–June ’06
[14]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Wednesday, June 21, 2006 — 1:15 to 4:15 p.m., only
ANSWER SHEET
I Male I Female Grade
Student
..............................................
Sex:
...........
Teacher
..............................................
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Wednesday, August 16, 2006 — 12:30 to 3:30 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
The use of any communications device is strictly prohibited when taking this
examination. If you use any communications device, no matter how briefly, your
examination will be invalidated and no score will be calculated for you.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
6 A compound is made up of iron and oxygen,
only. The ratio of iron ions to oxide ions is 2:3 in
this compound. The IUPAC name for this compound is
(1) triiron dioxide
(3) iron(III) oxide
(2) iron(II) oxide
(4) iron trioxide
1 Which statement correctly describes the charge
of the nucleus and the charge of the electron
cloud of an atom?
(1) The nucleus is positive and the electron
cloud is positive.
(2) The nucleus is positive and the electron
cloud is negative.
(3) The nucleus is negative and the electron
cloud is positive.
(4) The nucleus is negative and the electron
cloud is negative.
7 Which process is a chemical change?
(1) melting of ice
(2) boiling of water
(3) subliming of ice
(4) decomposing of water
2 Which Period 4 element has the most metallic
properties?
(1) As
(3) Ge
(2) Br
(4) Sc
8 Which substance contains bonds that involved the
transfer of electrons from one atom to another?
(1) CO2
(3) KBr
(2) NH3
(4) Cl2
3 Which property makes it possible to separate the
oxygen and the nitrogen from a sample of
liquefied air?
(1) boiling point
(3) hardness
(2) conductivity
(4) electronegativity
9 What is the total number of pairs of electrons
shared in a molecule of N2?
(1) one pair
(3) three pairs
(2) two pairs
(4) four pairs
4 Which statement explains why ozone gas, O3,
and oxygen gas, O2, have different properties?
(1) They are formed from different elements.
(2) They have different molecular structures.
(3) They have different oxidation numbers.
(4) They have different electronegativities.
10 Which formula represents a nonpolar molecule
containing polar covalent bonds?
(3) NH3
(1) H2O
(2) CCl4
(4) H2
5 Which statement is true about oxidation and
reduction in an electrochemical cell?
(1) Both occur at the anode.
(2) Both occur at the cathode.
(3) Oxidation occurs at the anode and reduction
occurs at the cathode.
(4) Oxidation occurs at the cathode and reduction occurs at the anode.
11 The degree of polarity of a chemical bond in a
molecule of a compound can be predicted by
determining the difference in the
(1) melting points of the elements in the compound
(2) densities of the elements in the compound
(3) electronegativities of the bonded atoms in a
molecule of the compound
(4) atomic masses of the bonded atoms in a
molecule of the compound
P.S./Chem.–Aug. ’06
[2]
18 The data table below gives the temperature and
pressure of four different gas samples, each in a
2-liter container.
12 Which statement best describes the shape and
volume of an aluminum cylinder at STP?
(1) It has a definite shape and a definite volume.
(2) It has a definite shape and no definite volume.
(3) It has no definite shape and a definite volume.
(4) It has no definite shape and no definite volume.
Temperature and Pressure of Gas Samples
13 Which two substances can not be broken down
by chemical change?
(1) C and CuO
(3) CO2 and CuO
(2) C and Cu
(4) CO2 and Cu
Temperature
(K)
Pressure
(atm)
He
300.
1.20
Ne
300.
1.00
CO2
200.
1.20
CH4
300.
1.00
Which two gas samples contain the same total
number of particles?
14 Which compound is insoluble in water?
(3) KClO3
(1) BaSO4
(2) CaCrO4
(4) Na2S
(1) CH4 and CO2
(2) CH4 and Ne
15 A sample of a gas is contained in a closed rigid
cylinder. According to kinetic molecular theory,
what occurs when the gas inside the cylinder is
heated?
(1) The number of gas molecules increases.
(2) The number of collisions between gas
molecules per unit time decreases.
(3) The average velocity of the gas molecules
increases.
(4) The volume of the gas decreases.
(3) He and CO2
(4) He and Ne
19 A chemical reaction is at equilibrium. Compared
to the rate of the forward reaction, the rate of the
reverse reaction is
(1) faster and more reactant is produced
(2) faster and more product is produced
(3) the same and the reaction has stopped
(4) the same and the reaction continues in both
directions
20 Which organic compound is a saturated hydrocarbon?
(1) ethyne
(3) ethanol
(2) ethene
(4) ethane
16 Which statement best describes how a catalyst
increases the rate of a reaction?
(1) The catalyst provides an alternate reaction
pathway with a higher activation energy.
(2) The catalyst provides an alternate reaction
pathway with a lower activation energy.
(3) The catalyst provides the same reaction
pathway with a higher activation energy.
(4) The catalyst provides the same reaction
pathway with a lower activation energy.
21 A substance is classified as an electrolyte because
(1) it has a high melting point
(2) it contains covalent bonds
(3) its aqueous solution conducts an electric
current
(4) its aqueous solution has a pH value of 7
17 The compounds 2-butanol and 2-butene both
contain
(1) double bonds, only (3) carbon atoms
(2) single bonds, only (4) oxygen atoms
P.S./Chem.–Aug. ’06
Gas
Sample
22 Half-reactions can be written to represent all
(1) double-replacement reactions
(2) neutralization reactions
(3) fission and fusion reactions
(4) oxidation and reduction reactions
[3]
[OVER]
23 Given the structural formulas:
Formula B
Formula A
H
H
H
C
C
H
H
H
OH
H
C
H
Formula C
H
O
C
H
H
H
H
O
H
C
C
C
H
Formula D
H
H
H
H
OH H
C
C
C
H
H
H
H
Which two formulas represent compounds that are isomers of each other?
(1) A and B
(3) B and D
(2) A and C
(4) C and D
27 Which equation represents a neutralization
reaction?
(1) 4Fe(s) + 3O2(g) → 2Fe2O3(s)
(2) 2H2(g) + O2(g) → 2H2O(ᐉ)
(3) HNO3(aq) + KOH(aq) →
KNO3(aq) + H2O(ᐉ)
(4) AgNO3(aq) + KCl(aq) →
KNO3(aq) + AgCl(s)
24 Given the balanced equation representing a
redox reaction:
2Al + 3Cu2+ → 2Al3+ + 3Cu
Which statement is true about this reaction?
(1) Each Al loses 2e– and each Cu2+ gains 3e–.
(2) Each Al loses 3e– and each Cu2+ gains 2e–.
(3) Each Al3+ gains 2e– and each Cu loses 3e–.
(4) Each Al3+ gains 3e– and each Cu loses 2e–.
28 Which notation of a radioisotope is correctly
paired with the notation of its emission particle?
(3) 16N and 11p
(1) 37Ca and 42He
25 Which conversion of energy always occurs in a
voltaic cell?
(1) light energy to chemical energy
(2) electrical energy to chemical energy
(3) chemical energy to light energy
(4) chemical energy to electrical energy
(2)
and +10 e
(4) 3H and –10e
29 Atoms of one element are converted to atoms of
another element through
(1) fermentation
(3) polymerization
(2) oxidation
(4) transmutation
26 The compound NaOH(s) dissolves in water to
yield
(1) hydroxide ions as the only negative ions
(2) hydroxide ions as the only positive ions
(3) hydronium ions as the only negative ions
(4) hydronium ions as the only positive ions
P.S./Chem.–Aug. ’06
235U
30 An atom of potassium-37 and an atom of
potassium-42 differ in their total number of
(1) electrons
(3) protons
(2) neutrons
(4) positrons
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
35 Which list of elements from Group 2 on the
Periodic Table is arranged in order of increasing
atomic radius?
(1) Be, Mg, Ca
(3) Ba, Ra, Sr
(2) Ca, Mg, Be
(4) Sr, Ra, Ba
31 What is the mass number of an atom that has six
protons, six electrons, and eight neutrons?
(1) 6
(3) 14
(2) 12
(4) 20
32 Which diagram represents the nucleus of an atom
27Al?
of 13
14 n
27 n
27 p
13 p
(1)
37 The percent composition by mass of magnesium
in MgBr2 (gram-formula mass = 184 grams/mole)
is equal to
(3)
14 n
40 n
13 p
13 p
(2)
36 Which half-reaction shows conservation of
charge?
(1) Cu + e– → Cu+
(3) Cu+ → Cu + e–
(2) Cu2+ + 2e– → Cu
(4) Cu2+ → Cu + 2e–
(2)
1
2
g
× 100
(3)
184
24
× 100
(2)
160.
184
× 100
(4)
184
160.
× 100
CaCO3(s) + 2HCl(aq) →
CaCl2(aq) + H2O(ᐉ) + CO2(g)
(4)
(3)
24
184
38 Given the balanced equation:
What is the total number of moles of CO2
formed when 20. moles of HCl is completely
consumed?
33 A student constructs a model for comparing the
masses of subatomic particles. The student selects
a small, metal sphere with a mass of 1 gram to
represent an electron. A sphere with which mass
would be most appropriate to represent a proton?
(1) 1 g
(1)
1
2000
(1) 5.0 mol
(2) 10. mol
(3) 20. mol
(4) 40. mol
39 What amount of heat is required to completely
melt a 29.95-gram sample of H2O(s) at 0°C?
(1) 334 J
(3) 1.00 × 103 J
(2) 2260 J
(4) 1.00 × 104 J
g
(4) 2000 g
34 Based on electronegativity values, which type of
elements tends to have the greatest attraction
for electrons in a bond?
(1) metals
(3) nonmetals
(2) metalloids
(4) noble gases
P.S./Chem.–Aug. ’06
[5]
[OVER]
44 Given the balanced equation representing a
reaction:
40 Which particle diagram represents a mixture of
element X and element Z, only?
CH4(g) + 2O2(g) → 2H2O(g) + CO2(g) + heat
Key
= atom of X
= atom of Z
(1)
Which statement is true about energy in this
reaction?
(1) The reaction is exothermic because it releases
heat.
(2) The reaction is exothermic because it absorbs
heat.
(3) The reaction is endothermic because it releases
heat.
(4) The reaction is endothermic because it absorbs
heat.
(3)
45 Given the reaction at equilibrium:
N2(g) + 3H2(g)
2NH3(g) + 91.8 kJ
What occurs when the concentration of H2(g) is
increased?
(2)
(1) The rate of the forward reaction increases
and the concentration of N2(g) decreases.
(2) The rate of the forward reaction decreases
and the concentration of N2(g) increases.
(3) The rate of the forward reaction and the
concentration of N2(g) both increase.
(4) The rate of the forward reaction and the
concentration of N2(g) both decrease.
(4)
41 An unsaturated aqueous solution of NH3 is at
90.°C in 100. grams of water. According to
Reference Table G, how many grams of NH3
could this unsaturated solution contain?
(1) 5 g
(3) 15 g
(2) 10. g
(4) 20. g
46 Given the potential energy diagram for a reaction:
Potential Energy
42 How many total moles of KNO3 must be dissolved
in water to make 1.5 liters of a 2.0 M solution?
(1) 0.50 mol
(3) 3.0 mol
(2) 2.0 mol
(4) 1.3 mol
43 Which statement explains why low temperature
and high pressure are required to liquefy
chlorine gas?
(1) Chlorine molecules have weak covalent
bonds.
(2) Chlorine molecules have strong covalent
bonds.
(3) Chlorine molecules have weak intermolecular forces of attraction.
(4) Chlorine molecules have strong intermolecular forces of attraction.
P.S./Chem.–Aug. ’06
3
2
4
1
Reaction Coordinate
Which interval on this diagram represents the
difference between the potential energy of the
products and the potential energy of the reactants?
(1) 1
(2) 2
[6]
(3) 3
(4) 4
49 Which list of the phases of H2O is arranged in
order of increasing entropy?
(1) ice, steam, and liquid water
(2) ice, liquid water, and steam
(3) steam, liquid water, and ice
(4) steam, ice, and liquid water
47 Based on bond type, which compound has the
highest melting point?
(3) CaCl2
(1) CH3OH
(2) C6H14
(4) CCl4
48 A 100.00-gram sample of naturally occurring
boron contains 19.78 grams of boron-10 (atomic
mass = 10.01 atomic mass units) and 80.22 grams
of boron-11 (atomic mass = 11.01 atomic mass
units). Which numerical setup can be used to
determine the atomic mass of naturally occurring
boron?
(1) (0.1978)(10.01) + (0.8022)(11.01)
50 Solution A has a pH of 3 and solution Z has
a pH of 6. How many times greater is the
hydronium ion concentration in solution A than
the hydronium ion concentration in solution Z?
(1) 100
(3) 3
(2) 2
(4) 1000
(2) (0.8022)(10.01) + (0.1978)(11.01)
(0.1978) (10.01)
(3)
(0.8022) (11.01)
(4)
(0.8022) (10.01)
(0.1978) (11.01)
P.S./Chem.–Aug. ’06
[7]
[OVER]
Part B–2
Answer all questions in this part.
Directions (51–65): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
51 In the space in your answer booklet, draw a Lewis electron-dot diagram for a sulfur
atom in the ground state. [1]
52 Explain, in terms of electron configuration, why selenium and sulfur have similar
chemical properties. [1]
Base your answers to questions 53 through 56 on the diagram below concerning the classification of matter.
Classification of Matter
Matter
Mixtures
Homogeneous
Substances
Elements
X
Z
53 What type of mixture is represented by X? [1]
54 What type of substance is represented by Z? [1]
55 Explain, in terms of particle arrangement, why NaCl(aq) is a homogeneous mixture. [1]
56 Given a mixture of sand and water, state one process that can be used to separate water
from the sand. [1]
P.S./Chem.–Aug. ’06
[8]
Base your answers to questions 57 through 60 on the information below.
An investigation was conducted to study the effect of the concentration of a reactant on
the total time needed to complete a chemical reaction. Four trials of the same reaction were
performed. In each trial the initial concentration of the reactant was different. The time
needed for the chemical reaction to be completed was measured. The data for each of the
four trials are shown in the table below.
Reactant Concentration and Reaction Time
Trial
Initial
Concentration
(M)
Reaction Time
(s)
1
2
3
4
0.020
0.015
0.010
0.005
11
14
23
58
57 On the grid in your answer booklet, mark an appropriate scale on the axis labeled
“Reaction Time (s).” An appropriate scale is one that allows a trend to be seen. [1]
58 On the same grid, plot the data from the data table. Circle and connect the points. [1]
Example:
59 State the effect of the concentration of the reactant on the rate of the chemical
reaction. [1]
60 In a different experiment involving the same reaction, it was found that an increase in
temperature increased the rate of the reaction. Explain this result in terms of collision
theory. [1]
Base your answers to questions 61 through 63 on the equation below, which represents an organic
compound reacting with bromine.
H H
H
C
H
C C H + Br2
H
H
H H
C
C C H
Br Br H
H
61 What is the IUPAC name for the organic compound that reacts with Br2? [1]
62 What type of organic reaction is represented by this equation? [1]
63 What is the gram-formula mass of the product in this reaction? [1]
P.S./Chem.–Aug. ’06
[9]
[OVER]
Base your answers to questions 64 and 65 on the information below.
A U-238 atom decays to a Pb-206 atom through a series of steps. Each point on the
graph below represents a nuclide and each arrow represents a nuclear decay mode.
Uranium Disintegration Series
238
Mass Number
234
230
226
222
218
214
210
206
202
82 83 84 85 86 87 88 89 90 91 92
Pb Bi Po At Rn Fr Ra Ac Th Pa U
Atomic Number and Chemical Symbol
64 Based on this graph, what particle is emitted during the nuclear decay of a Po-218
atom? [1]
65 Explain why the U-238 disintegration series ends with the nuclide Pb-206. [1]
P.S./Chem.–Aug. ’06
[10]
Part C
Answer all questions in this part.
Directions (66–85): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 66 and 67 on the information below.
Some radioisotopes used as tracers make it possible for doctors to see the images of
internal body parts and observe their functions. The table below lists information about
three radioisotopes and the body part each radioisotope is used to study.
Medical Uses of Some Radioisotopes
Radioisotope
Half-life
Decay Mode
Body Part
24Na
15 hours
beta
circulatory system
59Fe
44.5 days
beta
red blood cells
131I
8.1 days
beta
thyroid
66 Complete the equation in your answer booklet for the nuclear decay of the radioisotope
used to study red blood cells. Include both the atomic number and the mass number
for each missing particle. [1]
67 It could take up to 60. hours for a radioisotope to be delivered to the hospital from the
laboratory where it is produced. What fraction of an original sample of 24Na remains
unchanged after 60. hours? [1]
Base your answers to questions 68 through 71 on the information below.
A metal, M, was obtained from a compound in a rock sample. Experiments have determined that the element is a member of Group 2 on the Periodic Table of the Elements.
68 What is the phase of element M at STP?
[1]
69 Explain, in terms of electrons, why element M is a good conductor of electricity.
[1]
70 Explain why the radius of a positive ion of element M is smaller than the radius of an
atom of element M. [1]
71 Using the symbol M for the element, write the chemical formula for the compound that
forms when element M reacts with iodine. [1]
P.S./Chem.–Aug. ’06
[11]
[OVER]
Base your answers to questions 72 through 75 on the information below.
The graph below shows a compound being cooled at a constant rate starting in the
liquid phase at 75°C and ending at 15°C.
Temperature Changes Over Time
Temperature (°C)
90.
70.
50.
30.
10.
0
2
4
Time (min)
6
8
72 What is the freezing point of the compound, in degrees Celsius? [1]
73 State what is happening to the average kinetic energy of the particles of the sample
between minute 2 and minute 6. [1]
74 A different experiment was conducted with another sample of the same compound
starting in the solid phase. The sample was heated at a constant rate from 15°C to 75°C.
On the graph in your answer booklet, draw the resulting heating curve. [1]
75 What kelvin temperature is equal to 15°C? [1]
Base your answers to questions 76 and 77 on the information below.
Using burets, a student titrated a sodium hydroxide solution of unknown concentration
with a standard solution of 0.10 M hydrochloric acid. The data are recorded in the table below.
Titration Data
Solution
HCI(aq)
NaOH(aq)
Initial Buret Reading (mL)
15.50
5.00
Final Buret Reading (mL)
25.00
8.80
76 Determine both the total volume of HCl(aq) and the total volume of NaOH(aq) used in
the titration. [1]
77 In the space in your answer booklet, show a correct numerical setup for calculating the
molarity of the sodium hydroxide solution. [1]
P.S./Chem.–Aug. ’06
[12]
Base your answers to questions 78 and 79 on the information below.
Many esters have distinctive odors, which lead to their widespread use as artificial
flavorings and fragrances. For example, methyl butanoate has an odor like pineapple and
ethyl methanoate has an odor like raspberry.
78 In the space in your answer booklet, draw a structural formula for the ester that has an
odor like pineapple. [1]
79 What is a chemical name for the alcohol that reacts with methanoic acid to produce the
ester that has an odor like raspberry? [1]
Base your answers to questions 80 and 81 on the information below.
Three bottles of liquids labeled 1, 2, and 3 were found in a storeroom. One of the liquids
is known to be drain cleaner. Drain cleaners commonly contain KOH or NaOH. The pH of
each liquid at 25°C was determined with a pH meter. The table below shows the test results.
pH Test Results
Bottle
pH of Liquid
1
3.8
2
7.0
3
12.8
80 Explain how the pH results in this table enable a student to correctly conclude that
bottle 3 contains the drain cleaner. [1]
81 Explain, in terms of the pH values, why thymol blue is not a suitable indicator to
distinguish between the contents of bottle 1 and bottle 2. [1]
P.S./Chem.–Aug. ’06
[13]
[OVER]
Base your answers to questions 82 through 85 on the information below.
A student places a 2.50-gram sample of magnesium metal in a bottle and fits the bottle
with a 2-hole stopper as shown in the diagram. Hydrochloric acid is added to the bottle,
causing a reaction. As the reaction proceeds, hydrogen gas travels through the tubing to an
inverted bottle filled with water, displacing some of the water in the bottle.
HCl(aq)
(reactant)
H2(g)
Water
H2(g)
Water
Mg(s)
(reactant)
82 Balance the equation in your answer booklet for the reaction of magnesium and
hydrochloric acid, using the smallest whole-number coefficients. [1]
83 Identify the type of chemical reaction that occurs when magnesium reacts with
hydrochloric acid. [1]
84 In the space in your answer booklet, show a correct numerical setup for calculating the
number of moles of magnesium used in the experiment. [1]
85 Based on Reference Table J, explain why Ag(s) will not react with HCl(aq) to generate
H2(g). [1]
P.S./Chem.–Aug. ’06
[14]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Wednesday, August 16, 2006 — 12:30 to 3:30 p.m., only
ANSWER SHEET
I Male I Female Grade
Student
..............................................
Sex:
...........
Teacher
..............................................
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Thursday, January 25, 2007 — 1:15 to 4:15 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
The use of any communications device is strictly prohibited when taking this
examination. If you use any communications device, no matter how briefly, your
examination will be invalidated and no score will be calculated for you.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
1 Which subatomic particles are located in the
nucleus of a neon atom?
(1) electrons and positrons
(2) electrons and neutrons
(3) protons and neutrons
(4) protons and electrons
6 An atom of argon rarely bonds to an atom of
another element because an argon atom has
(1) 8 valence electrons
(2) 2 electrons in the first shell
(3) 3 electron shells
(4) 22 neutrons
2 The total mass of the protons in an atom of
gold-198 is approximately
(1) 79 atomic mass units
(2) 119 atomic mass units
(3) 198 atomic mass units
(4) 277 atomic mass units
7 The elements on the Periodic Table are
arranged in order of increasing
(1) boiling point
(3) atomic number
(2) electronegativity
(4) atomic mass
8 Which element is classified as a nonmetal?
(1) Be
(3) Si
(2) Al
(4) Cl
3 In a calcium atom in the ground state, the
electrons that possess the least amount of energy
are located in the
(1) first electron shell
(2) second electron shell
(3) third electron shell
(4) fourth electron shell
9 Solid samples of the element phosphorus can be
white, black, or red in color. The variations in
color are due to different
(1) atomic masses
(2) molecular structures
(3) ionization energies
(4) nuclear charges
4 Which group of atomic models is listed in
historical order from the earliest to the most
recent?
(1) hard-sphere model, wave-mechanical model,
electron-shell model
(2) hard-sphere model, electron-shell model,
wave-mechanical model
(3) electron-shell model, wave-mechanical
model, hard-sphere model
(4) electron-shell model, hard-sphere model,
wave-mechanical model
10 Given the balanced equation representing the
reaction between propane and oxygen:
C3H8 + 5O2 → 3CO2 + 4H2O
According to this equation, which ratio of oxygen
to propane is correct?
5 Which isotopic notation represents an atom of
carbon-14?
(1) 68 C
(3) 146 C
(2)
8C
6
P.S./Chem.–Jan. ’07
(4)
14 C
6
[2]
(1)
5 grams O2
1 gram C3H8
(3)
10 grams O2
11 grams C3H8
(2)
5 moles O2
1 mole C3H8
(4)
10 moles O2
11 moles C3H8
16 The balanced equation below represents a molecule
of bromine separating into two bromine atoms.
11 Lithium and potassium have similar chemical
properties because the atoms of both elements
have the same
(1) mass number
(2) atomic number
(3) number of electron shells
(4) number of valence electrons
Br2 → Br + Br
What occurs during this change?
(1) Energy is absorbed and a bond is formed.
(2) Energy is absorbed and a bond is broken.
(3) Energy is released and a bond is formed.
(4) Energy is released and a bond is broken.
12 Which two substances are covalent compounds?
(1) C6H12O6(s) and KI(s)
(2) C6H12O6(s) and HCl(g)
(3) KI(s) and NaCl(s)
(4) NaCl(s) and HCl(g)
17 Which substance can be decomposed by chemical
means?
(1) tungsten
(3) krypton
(2) antimony
(4) methane
13 Which substance, when dissolved in water,
forms a solution that conducts an electric current?
(1) C2H5OH
(3) C12H22O11
(2) C6H12O6
(4) CH3COOH
18 Bronze contains 90 to 95 percent copper and 5 to
10 percent tin. Because these percentages can
vary, bronze is classified as
(1) a compound
(3) a mixture
(2) an element
(4) a substance
14 Given the diagram representing a reaction:
1n
0
235
92 U
137
52 Te
97
40 Zr
19 Compared to a 2.0 M aqueous solution of NaCl
at 1 atmosphere, a 3.0 M aqueous solution of
NaCl at 1 atmosphere has a
(1) lower boiling point and a higher freezing
point
(2) lower boiling point and a lower freezing
point
(3) higher boiling point and a higher freezing
point
(4) higher boiling point and a lower freezing
point
1n
0
1n
0
Which phrase best describes this type of reaction
and the overall energy change that occurs?
(1) nuclear, and energy is released
(2) nuclear, and energy is absorbed
(3) chemical, and energy is released
(4) chemical, and energy is absorbed
20 In which reaction are electrons transferred from
one reactant to another reactant?
(1) 2Ca(s) + O2(g) → 2CaO(s)
(2) AgNO3(aq) + KCl(aq) →
AgCl(s) + KNO3(aq)
(3) HCl(aq) + NaOH(aq) →
NaCl(aq) + H2O(ᐉ)
(4) H3O+(aq) + OH–(aq) → 2H2O(ᐉ)
15 Compared to a phosphorus atom, a P3– ion has
(1) more electrons and a larger radius
(2) more electrons and a smaller radius
(3) fewer electrons and a larger radius
(4) fewer electrons and a smaller radius
P.S./Chem.–Jan. ’07
[3]
[OVER]
25 Two substances have different physical and
chemical properties. Both substances have
molecules that contain two carbon atoms, one
oxygen atom, and six hydrogen atoms. These
two substances must be
(1) isomers of each other
(2) isotopes of each other
(3) the same compound
(4) the same hydrocarbon
21 Which statement must be true for any chemical
reaction at equilibrium?
(1) The concentration of the products is greater
than the concentration of the reactants.
(2) The concentration of the products is less
than the concentration of the reactants.
(3) The concentration of the products and the
concentration of the reactants are equal.
(4) The concentration of the products and the
concentration of the reactants are constant.
26 Given the balanced equation representing a
reaction:
22 Given the structural formula:
H H H H
CH3CH2CH3 + Br2 → CH3CH2CH2Br + HBr
O
H C C C C C OH
H H
This organic reaction is best classified as
(1) an addition reaction
(2) an esterification reaction
(3) a polymerization reaction
(4) a substitution reaction
H H
What is the IUPAC name of this compound?
(1) pentanal
(3) methyl pentanoate
(2) pentanol
(4) pentanoic acid
27 In terms of energy and entropy, systems in
nature tend to undergo changes toward
(1) higher energy and higher entropy
(2) higher energy and lower entropy
(3) lower energy and higher entropy
(4) lower energy and lower entropy
23 Which structural formula represents an unsaturated hydrocarbon?
H
H
H C
C
H
H
H
H
H
C
H
H
(1)
H
H
C
OH
(2)
H
O
H
C
H
(4)
29 Which compound has hydrogen bonding
between its molecules?
(1) CH4
(3) KH
(2) CaH2
(4) NH3
24 Which group of nuclear emissions is listed in
order of increasing charge?
(1) alpha particle, beta particle, gamma radiation
(2) gamma radiation, alpha particle, beta
particle
(3) positron, alpha particle, neutron
(4) neutron, positron, alpha particle
P.S./Chem.–Jan. ’07
C
What is the total number of electrons shared in
the bond between the two carbon atoms?
(1) 6
(3) 3
(2) 2
(4) 4
H
C
H
28 Given the structural formula:
(3)
O
C
C
30 Which ion is the only negative ion produced by
an Arrhenius base in water?
(3) OH–
(1) NO3–
(2) Cl–
(4) H–
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
36 Given the balanced equation representing a
reaction:
31 When the elements in Group 1 are considered
in order from top to bottom, each successive
element at standard pressure has
(1) a higher melting point and a higher boiling
point
(2) a higher melting point and a lower boiling
point
(3) a lower melting point and a higher boiling
point
(4) a lower melting point and a lower boiling
point
4NH3 + 5O2 → 4NO + 6H2O
What is the minimum
O2 that are needed to
16 moles of NH3?
(1) 16 mol
(2) 20. mol
(3) 64 mol
(4) 80. mol
37 Which Lewis electron-dot diagram correctly
represents a hydroxide ion?
32 Which isotopic notation identifies a metalloid
that is matched with the corresponding number
of protons in each of its atoms?
(1) 24Mg and 12 protons
(2) 28Si and 14 protons
(3) 75As and 75 protons
(4) 80Br and 80 protons
–
–
OH
O H
(1)
(3)
–
OH
(2)
33 At STP, which list of elements contains a solid, a
liquid, and a gas?
(1) Hf, Hg, He
(2) Cr, Cl2, C
number of moles of
completely react with
–
O H
(4)
38 A 10.0-gram sample of which element has the
smallest volume at STP?
(1) aluminum
(3) titanium
(2) magnesium
(4) zinc
(3) Ba, Br2, B
(4) Se, Sn, Sr
34 Element X reacts with iron to form two different
compounds with the formulas FeX and Fe2X3.
To which group on the Periodic Table does
element X belong?
(1) Group 8
(3) Group 13
(2) Group 2
(4) Group 16
39 At which temperature would atoms of a He(g)
sample have the greatest average kinetic energy?
(1) 25°C
(3) 273 K
(2) 37°C
(4) 298 K
35 The molar mass of Ba(OH)2 is
(1) 154.3 g
(3) 171.3 g
(2) 155.3 g
(4) 308.6 g
P.S./Chem.–Jan. ’07
[5]
[OVER]
40 A student prepares four aqueous solutions, each with a different solute. The mass of each dissolved solute
is shown in the table below.
Mass of Dissolved Solute
for Four Aqueous Solutions
Solution
Number
Solute
Mass of Dissolved Solute
(per 100. g of H2O at 20.°C)
1
Kl
120. g
2
NaNO3
88 g
3
KCl
25 g
4
KClO3
5g
Which solution is saturated?
(1) 1
(2) 2
(3) 3
(4) 4
44 Given the system at equilibrium:
41 At room temperature, a mixture of sand and
water can be separated by
(1) ionization
(3) filtration
(2) combustion
(4) sublimation
2POCl3(g) + energy
Which changes occur when O2(g) is added to
this system?
(1) The equilibrium shifts to the right and the
concentration of PCl3(g) increases.
(2) The equilibrium shifts to the right and the
concentration of PCl3(g) decreases.
(3) The equilibrium shifts to the left and the
concentration of PCl3(g) increases.
(4) The equilibrium shifts to the left and the
concentration of PCl3(g) decreases.
42 Given the balanced equation representing a
reaction at 101.3 kPa and 298 K:
N2(g) + 3H2(g) → 2NH3(g) + 91.8 kJ
Which statement is true about this reaction?
(1) It is exothermic and ΔH equals –91.8 kJ.
(2) It is exothermic and ΔH equals +91.8 kJ.
(3) It is endothermic and ΔH equals –91.8 kJ.
(4) It is endothermic and ΔH equals +91.8 kJ.
45 What is the oxidation number of chromium in
the chromate ion, CrO42–?
(1) +6
(3) +3
(2) +2
(4) +8
43 Which balanced equation represents a phase
equilibrium?
(1) H2(g) + I2(g)
2HI(g)
(2) 2NO2(g)
N2O4(g)
(3) Cl2(g)
Cl2(ᐉ)
(4) 3O2(g)
2O3(g)
P.S./Chem.–Jan. ’07
2PCl3(g) + O2(g)
[6]
46 Given the balanced equation representing a
reaction:
49 If
1
8
of an original sample of krypton-74 remains
unchanged after 34.5 minutes, what is the
half-life of krypton-74?
(1) 11.5 min
(3) 34.5 min
(2) 23.0 min
(4) 46.0 min
H2SO4(aq) + 2KOH(aq) → K2SO4(aq) + 2H2O(ᐉ)
Which type of reaction is represented by this
equation?
(1) decomposition
(3) single replacement
(2) neutralization
(4) synthesis
50 Given the nuclear equation:
253
99Es
47 In which 0.01 M solution is phenolphthalein
pink?
(1) CH3OH(aq)
(3) CH3COOH(aq)
(2) Ca(OH)2(aq)
(4) HNO3(aq)
+ X → 10 n + 256
101Md
Which particle is represented by X?
(3) 10 n
(1) 42 He
(2) –10 e
(4) +10 e
48 As the pH of a solution is changed from 3 to 6,
the concentration of hydronium ions
(1) increases by a factor of 3
(2) increases by a factor of 1000
(3) decreases by a factor of 3
(4) decreases by a factor of 1000
P.S./Chem.–Jan. ’07
[7]
[OVER]
Part B–2
Answer all questions in this part.
Directions (51–66): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
51 Naturally occurring boron is composed of two isotopes. The percent abundance and
the mass of each isotope are listed below.
• 19.9% of the boron atoms have a mass of 10.013 atomic mass units.
• 80.1% of the boron atoms have a mass of 11.009 atomic mass units.
In the space in your answer booklet, calculate the atomic mass of boron. Your response
must include both a correct numerical setup and the calculated result. [2]
Base your answers to questions 52 and 53 on the information below.
During a laboratory activity, a student reacted a piece of zinc with 0.1 M HCl(aq).
52 Complete the equation in your answer booklet by writing the formula of the missing
product. [1]
53 Based on Reference Table J, identify one metal that does not react spontaneously with
HCl(aq). [1]
54 A hydrated compound contains water molecules within its crystal structure. The
percent composition by mass of water in the hydrated compound CaSO4•2H2O has an
accepted value of 20.9%. A student did an experiment and determined that the
percent composition by mass of water in CaSO4•2H2O was 21.4%.
In the space in your answer booklet, calculate the percent error of the student’s
experimental result. Your response must include both a correct numerical setup and
the calculated result. [2]
P.S./Chem.–Jan. ’07
[8]
Base your answers to questions 55 through 57 on the information below.
The particle diagrams below represent the reaction between two nonmetals, A2 and Q2.
Key
= Atom of element A
= Atom of element Q
Reactants
Product
55 Using the symbols A and Q, write the chemical formula of the product. [1]
56 Identify the type of chemical bond between an atom of element A and an atom of
element Q. [1]
57 Compare the total mass of the reactants to the total mass of the product. [1]
58 A potential energy diagram for a chemical reaction is shown in your answer booklet. On
this diagram, draw a curve to show how the potential energy diagram will change when
a catalyst is added to the reaction. [1]
59 Explain, in terms of collision theory, why an increase in temperature increases the rate
of a chemical reaction. [1]
60 An aqueous solution contains 300. parts per million of KOH. Determine the number of
grams of KOH present in 1000. grams of this solution. [1]
P.S./Chem.–Jan. ’07
[9]
[OVER]
Base your answers to questions 61 through 63 on the diagram below. The diagram shows a voltaic cell with
copper and aluminum electrodes immediately after the external circuit is completed.
Voltaic Cell
V
Voltmeter
Wire
Salt
bridge
Cu(s) electrode
2+
Al(s) electrode
3+
Cu (aq)
Al (aq)
Half-cell 1
Half-cell 2
61 Balance the redox equation in your answer booklet, using the smallest whole-number
coefficients. [1]
62 As this voltaic cell operates, the mass of the Al(s) electrode decreases. Explain, in terms
of particles, why this decrease in mass occurs. [1]
63 Explain the function of the salt bridge. [1]
64 Identify two indicators from Reference Table M that are yellow in solutions with a pH
of 5.5. [1]
65 Explain, in terms of molecular structure or distribution of charge, why a molecule of
methane is nonpolar. [1]
66 A liquid boils when the vapor pressure of the liquid equals the atmospheric pressure on
the surface of the liquid. Using Reference Table H, determine the boiling point of
water when the atmospheric pressure is 90. kPa. [1]
P.S./Chem.–Jan. ’07
[10]
Part C
Answer all questions in this part.
Directions (67–83): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 67 through 70 on the information below, which describes the proposed
discovery of element 118.
In 1999, a nuclear chemist and his team announced they had discovered a new
element by crashing krypton atoms into lead. The new element, number 118, was
assigned the name ununoctium and the symbol Uuo. One possible isotope of
ununoctium could have been Uuo-291.
However, the discovery of Uuo was not confirmed because other scientists
could not reproduce the experimental results published by the nuclear chemist and
his team. In 2006, another team of scientists claimed that they produced Uuo. This
claim has yet to be confirmed.
Adapted from Discover January 2002
67 Based on atomic number, in which group on the Periodic Table would element 118 be
placed? [1]
68 What would be the total number of neutrons present in a theoretical atom of Uuo-291?
[1]
69 What would be the total number of electrons present in a theoretical atom of Uuo-291?
[1]
70 Explain why being able to reproduce scientific results is an important component of
scientific research. [1]
P.S./Chem.–Jan. ’07
[11]
[OVER]
Base your answers to questions 71 through 74 on the information below.
Have you ever seen an insect called a water strider “skating” across the surface
of a calm pond? Have you ever “floated” a sewing needle on the water in a glass? If
you have, then you’ve observed one of water’s many amazing properties.
Water’s surface tension keeps the water strider and the sewing needle from
sinking into the water. Simply stated, the surface tension is due to the forces that
hold the water molecules together. Without these intermolecular forces, the water
strider and the sewing needle would sink below the surface of the water.
The surface tension of water at various temperatures is given in the data table
below.
Surface Tension at Different Water Temperatures
Water Temperature
(°C)
Surface Tension
(mN/m)
10.
74.2
25
72.0
50.
67.9
75
63.6
100.
58.9
71 On the grid in your answer booklet, plot the data from the data table. Circle and
connect the five points. [1]
Example:
72 According to your graph, what is the surface tension of water at 60.°C? [1]
73 State the relationship between the surface tension and the temperature of water. [1]
74 The surface tension of liquid tetrachloromethane, CCl4, at 25°C is 26.3 millinewtons/meter (mN/m). Compare the intermolecular forces between molecules of
CCl4 to the intermolecular forces between molecules of water, H2O, at 25°C. [1]
P.S./Chem.–Jan. ’07
[12]
Base your answers to questions 75 through 77 on the information below.
A rigid cylinder is fitted with a movable piston. The cylinder contains a
sample of helium gas, He(g), which has an initial volume of 125.0 milliliters and an
initial pressure of 1.0 atmosphere, as shown below. The temperature of the helium
gas sample is 20.0°C.
Handle
Movable
piston
1.0
150.0 mL
125.0 mL
2.0
0
100.0 mL
3.0
Pressure
gauge
ATM
75.0 mL
Rigid
cylinder
50.0 mL
25.0 mL
75 Express the initial volume of the helium gas sample, in liters. [1]
76 The piston is pushed further into the cylinder. In the space in your answer booklet,
show a correct numerical setup for calculating the volume of the helium gas that is
anticipated when the reading on the pressure gauge is 1.5 atmospheres. The temperature of the helium gas remains constant. [1]
77 Helium gas is removed from the cylinder and a sample of nitrogen gas, N2(g), is added
to the cylinder. The nitrogen gas has a volume of 125.0 milliliters and a pressure of
1.0 atmosphere at 20.0°C. Compare the number of particles in this nitrogen gas
sample to the number of particles in the original helium gas sample. [1]
P.S./Chem.–Jan. ’07
[13]
[OVER]
Base your answers to questions 78 through 81 on the information below.
In preparing to titrate an acid with a base, a student puts on goggles and an
apron. The student uses burets to dispense and measure the acid and the base
in the titration. In each of two trials, a 0.500 M NaOH(aq) solution is added to a
flask containing a volume of HCl(aq) solution of unknown concentration.
Phenolphthalein is the indicator used in the titration. The calculated volumes used
for the two trials are recorded in the table below.
Volumes of Base and Acid Used in Titration Trials
Solution
(aq)
NaOH
HCl
Trial 1
Trial 2
Molarity
(M)
Volume Used
(mL)
Volume Used
(mL)
0.500
17.03
16.87
?
10.22
10.12
78 Write a chemical name for the acid used in the titration. [1]
79 Using the volumes from trial 1, determine the molarity of the HCl(aq) solution. [1]
80 Based on the information given in the table, how many significant figures should be
shown in the calculated molarity of the HCl(aq) solution used in trial 2? [1]
81 Identify one additional safety precaution the student should have taken before
performing the titration. [1]
P.S./Chem.–Jan. ’07
[14]
Base your answers to questions 82 and 83 on the information below.
A gasoline engine burns gasoline in the presence of excess oxygen to form
carbon dioxide and water. The main components of gasoline are isomers of octane. A
structural formula of octane is shown below.
H H H H H H H H
H C C C C C C C C H
H H H H H H H H
One isomer of octane is 2,2,4-trimethylpentane.
82 In the space in your answer booklet, draw a structural formula for 2,2,4-trimethylpentane.
[1]
83 Explain, in terms of the arrangement of particles, why the entropy of gasoline vapor is
greater than the entropy of liquid gasoline. [1]
P.S./Chem.–Jan. ’07
[15]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Thursday, January 25, 2007 — 1:15 to 4:15 p.m., only
ANSWER SHEET
I Male I Female Grade
Student
..............................................
Sex:
...........
Teacher
..............................................
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Thursday, August 16, 2007 — 12:30 to 3:30 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
The use of any communications device is strictly prohibited when taking this
examination. If you use any communications device, no matter how briefly, your
examination will be invalidated and no score will be calculated for you.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
5 Which element has both metallic and nonmetallic
properties?
(1) Rb
(3) Si
(2) Rn
(4) Sr
1 What was concluded about the structure of the
atom as the result of the gold foil experiment?
(1) A positively charged nucleus is surrounded
by positively charged particles.
(2) A positively charged nucleus is surrounded
by mostly empty space.
(3) A negatively charged nucleus is surrounded
by positively charged particles.
(4) A negatively charged nucleus is surrounded
by mostly empty space.
6 The carbon atoms in graphite and the carbon
atoms in diamond have different
(1) atomic numbers
(2) atomic masses
(3) electronegativities
(4) structural arrangements
2 An atom is electrically neutral because the
(1) number of protons equals the number of
electrons
(2) number of protons equals the number of
neutrons
(3) ratio of the number of neutrons to the
number of electrons is 1:1
(4) ratio of the number of neutrons to the
number of protons is 2:1
7 Atoms of which element have the greatest
tendency to gain electrons?
(1) bromine
(3) fluorine
(2) chlorine
(4) iodine
8 Which statement describes a chemical property
of the element magnesium?
(1) Magnesium is malleable.
(2) Magnesium conducts electricity.
(3) Magnesium reacts with an acid.
(4) Magnesium has a high boiling point.
3 How do the energy and the most probable
location of an electron in the third shell of an
atom compare to the energy and the most
probable location of an electron in the first shell
of the same atom?
(1) In the third shell, an electron has more
energy and is closer to the nucleus.
(2) In the third shell, an electron has more
energy and is farther from the nucleus.
(3) In the third shell, an electron has less
energy and is closer to the nucleus.
(4) In the third shell, an electron has less
energy and is farther from the nucleus.
9 Matter that is composed of two or more different
elements chemically combined in a fixed
proportion is classified as
(1) a compound
(3) a mixture
(2) an isotope
(4) a solution
10 Given the balanced equation representing a
reaction:
2CO(g) + O2(g) → 2CO2(g)
4 Which element is a solid at STP and a good
conductor of electricity?
(1) iodine
(3) nickel
(2) mercury
(4) sulfur
P.S./Chem.–Aug. ’07
What is the mole ratio of CO(g) to CO2(g) in
this reaction?
(1) 1:1
(3) 2:1
(2) 1:2
(4) 3:2
[2]
11 Given the balanced equation representing a
reaction:
19 At STP, which sample contains the same number
of molecules as 11.2 liters of CO2(g) at STP?
(3) 11.2 L of N2(g)
(1) 5.6 L of NO2(g)
(4) 22.4 L of CO(g)
(2) 7.5 L of H2(g)
H+(aq) + OH–(aq) → H2O(ᐉ) + 55.8 kJ
In this reaction there is conservation of
(1) mass, only
(2) mass and charge, only
(3) mass and energy, only
(4) mass, charge, and energy
20 A sample of gas is held at constant pressure.
Increasing the kelvin temperature of this gas
sample causes the average kinetic energy of its
molecules to
(1) decrease and the volume of the gas sample
to decrease
(2) decrease and the volume of the gas sample
to increase
(3) increase and the volume of the gas sample to
decrease
(4) increase and the volume of the gas sample to
increase
12 Which polyatomic ion contains the greatest
number of oxygen atoms?
(1) acetate
(3) hydroxide
(2) carbonate
(4) peroxide
13 Which formula represents an ionic compound?
(3) CH3OH
(1) H2
(4) NH4Cl
(2) CH4
21 Given the balanced equation representing a
reaction:
14 An ion of which element has a larger radius than
an atom of the same element?
(1) aluminum
(3) magnesium
(2) chlorine
(4) sodium
Cl2(g) → Cl(g) + Cl(g)
What occurs during this change?
(1) Energy is absorbed and a bond is broken.
(2) Energy is absorbed and a bond is formed.
(3) Energy is released and a bond is broken.
(4) Energy is released and a bond is formed.
15 Which statement must be true when solution
equilibrium occurs?
(1) The solution is at STP.
(2) The solution is supersaturated.
(3) The concentration of the solution remains
constant.
(4) The masses of the dissolved solute and the
undissolved solute are equal.
22 A molecule of butane and a molecule of
2-butene both have the same total number of
(1) carbon atoms
(3) single bonds
(2) hydrogen atoms
(4) double bonds
23 Which general formula represents the homologous series of hydrocarbons that includes the
compound l-heptyne?
(1) CnH2n–6
(3) CnH2n
(2) CnH2n–2
(4) CnH2n+2
16 Which liquid has the highest vapor pressure at
75°C?
(1) ethanoic acid
(3) propanone
(2) ethanol
(4) water
17 What is the total number of different elements
present in NH4NO3?
(1) 7
(3) 3
(2) 9
(4) 4
24 Which two compounds are isomers of each
other?
(1) CH3CH2COOH and CH3COOCH2CH3
(2) CH3CH2CHO and CH3COCH3
(3) CH3CHBrCH3 and CH2BrCHBrCH3
(4) CH3CHOHCH3 and CH3CHOHCH2OH
18 Which sample of matter is a single substance?
(1) air
(3) hydrochloric acid
(2) ammonia gas
(4) salt water
P.S./Chem.–Aug. ’07
[3]
[OVER]
25 Which formula represents an unsaturated
hydrocarbon?
H
H
H
C
C H
H
H
H
(1)
H
(2)
H
C
C H
H
Cl
28 What is the decay mode of 37K?
(3) γ
(1) β–
(2) β+
(4) α
(3)
H
H
H
H
C C
H
H
27 Which compound is an Arrhenius acid?
(3) NaOH
(1) H2SO4
(2) KCl
(4) NH3
29 Which nuclear emission has the greatest penetrating power?
(1) alpha particle
(3) gamma radiation
(2) beta particle
(4) positron
H
C C
Cl
(4)
30 What is the mass number of an alpha particle?
(1) 1
(3) 0
(2) 2
(4) 4
26 Which formula represents a hydronium ion?
(3) OH–
(1) H3O+
(2) NH4+
(4) HCO3–
P.S./Chem.–Aug. ’07
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
31 What is the net charge on an ion that has
9 protons, 11 neutrons, and 10 electrons?
(1) 1+
(3) 1–
(2) 2+
(4) 2–
36 At standard pressure, a certain compound has a
low boiling point and is insoluble in water. At
STP, this compound most likely exists as
(1) ionic crystals
(2) metallic crystals
(3) nonpolar molecules
(4) polar molecules
32 Which two particles make up most of the mass
of a hydrogen-2 atom?
(1) electron and neutron
(2) electron and proton
(3) proton and neutron
(4) proton and positron
37 The table below shows mass and volume data
for four samples of substances at 298 K and
1 atmosphere.
Masses and Volumes of Four Samples
33 Which statement explains why sulfur is classified
as a Group 16 element?
(1) A sulfur atom has 6 valence electrons.
(2) A sulfur atom has 16 neutrons.
(3) Sulfur is a yellow solid at STP.
(4) Sulfur reacts with most metals.
Sample
A
30.
60.
B
40.
50.
C
45.
90.
D
90.
120.
Which two samples could consist of the same
substance?
(1) A and B
(3) B and C
(2) A and C
(4) C and D
34 How do the atomic radius and metallic properties of sodium compare to the atomic radius and
metallic properties of phosphorus?
(1) Sodium has a larger atomic radius and is
more metallic.
(2) Sodium has a larger atomic radius and is less
metallic.
(3) Sodium has a smaller atomic radius and is
more metallic.
(4) Sodium has a smaller atomic radius and is
less metallic.
38 Which group on the Periodic Table of the
Elements contains elements that react with
oxygen to form compounds with the general
formula X2O?
(1) Group 1
(3) Group 14
(2) Group 2
(4) Group 18
35 A compound has a molar mass of 90. grams per
mole and the empirical formula CH2O. What is
the molecular formula of this compound?
(3) C3H6O3
(1) CH2O
(2) C2H4O2
(4) C4H8O4
P.S./Chem.–Aug. ’07
Mass (g) Volume (mL)
39 An unsaturated solution is formed when
80. grams of a salt is dissolved in 100. grams of
water at 40.°C. This salt could be
(1) KCl
(3) NaCl
(2) KNO3
(4) NaNO3
[5]
[OVER]
44 Given the unbalanced ionic equation:
40 Which kelvin temperature is equal to 56°C?
(1) –329 K
(3) 217 K
(2) –217 K
(4) 329 K
3Mg + ____ Fe3+ → 3Mg2+ + ____ Fe
When this equation is balanced, both Fe3+ and
Fe have a coefficient of
(1) 1, because a total of 6 electrons is transferred
(2) 2, because a total of 6 electrons is transferred
(3) 1, because a total of 3 electrons is transferred
(4) 2, because a total of 3 electrons is transferred
41 Given the formula of a substance:
H
H
C C
H
H
H
C C
H
45 A student collects the materials and equipment
below to construct a voltaic cell.
What is the total number of shared electrons in
a molecule of this substance?
(1) 22
(3) 9
(2) 11
(4) 6
•
•
•
•
•
•
42 Given the balanced equation representing the
reaction occurring in a voltaic cell:
Zn(s) + Pb2+(aq) → Zn2+(aq) + Pb(s)
two 250-mL beakers
wire and a switch
one strip of magnesium
one strip of copper
125 mL of 0.20 M Mg(NO3)2(aq)
125 mL of 0.20 M Cu(NO3)2(aq)
Which additional item is required for the
construction of the voltaic cell?
(1) an anode
(3) a cathode
(2) a battery
(4) a salt bridge
In the completed external circuit, the electrons
flow from
(1) Pb(s) to Zn(s)
(2) Pb2+(aq) to Zn2+(aq)
(3) Zn(s) to Pb(s)
(4) Zn2+(aq) to Pb2+(aq)
46 Given the balanced equation representing a
reaction:
Zn(s) + 2HCl(aq) → H2(g) + ZnCl2(aq)
43 Which balanced equation represents a redox
reaction?
Which set of reaction conditions produces H2(g)
at the fastest rate?
(1) a 1.0-g lump of Zn(s) in 50. mL of
0.5 M HCl(aq) at 20.°C
(2) a 1.0-g lump of Zn(s) in 50. mL of
0.5 M HCl(aq) at 30.°C
(3) 1.0 g of powdered Zn(s) in 50. mL of
1.0 M HCl(aq) at 20.°C
(4) 1.0 g of powdered Zn(s) in 50. mL of
1.0 M HCl(aq) at 30.°C
(1) CuCO3(s) → CuO(s) + CO2(g)
(2) 2KClO3(s) → 2KCl(s) + 3O2(g)
(3) AgNO3(aq) + KCl(aq) →
AgCl(s) + KNO3(aq)
(4) H2SO4(aq) + 2KOH(aq) →
K2SO4(aq) + 2H2O(ᐉ)
P.S./Chem.–Aug. ’07
[6]
49 Which nuclear equation represents a natural
transmutation?
(1) 94Be + 11H → 63Li + 42He
47 The table below shows the color of the indicators methyl orange and litmus in two samples of
the same solution.
(2)
Results of Acid-Base Indicator Tests
Indicator
Color Result from the
Indicator Test
methyl orange
yellow
litmus
red
(3)
(4)
27
4
30
1
13Al + 2He → 15P + 0n
14
4
17
1
7N + 2He → 8O + 1H
235
231
4
92U → 90Th + 2He
50 A nuclear fission reaction and a nuclear fusion
reaction are similar because both reactions
(1) form heavy nuclides from light nuclides
(2) form light nuclides from heavy nuclides
(3) release a large amount of energy
(4) absorb a large amount of energy
Which pH value is consistent with the indicator
results?
(1) 1
(3) 3
(2) 5
(4) 10
48 What is the pH of a solution that has a hydronium
ion concentration 100 times greater than a
solution with a pH of 4?
(1) 5
(3) 3
(2) 2
(4) 6
P.S./Chem.–Aug. ’07
[7]
[OVER]
Part B–2
Answer all questions in this part.
Directions (51–66): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
51 What is the oxidation number of nitrogen in NO(g)? [1]
52 Write an electron configuration for an atom of aluminum-27 in an excited state. [1]
53 What color is bromcresol green after it is added to a sample of NaOH(aq)? [1]
Base your answers to questions 54 through 56 on the information below.
The accepted values for the atomic mass and percent natural abundance of each
naturally occurring isotope of silicon are given in the data table below.
Naturally Occurring Isotopes of Silicon
Isotope
Atomic Mass
(atomic mass units)
Percent Natural
Abundance (%)
Si-28
27.98
92.22
Si-29
28.98
4.69
Si-30
29.97
3.09
54 Determine the total number of neutrons in an atom of Si-29. [1]
55 In the space in your answer booklet, show a correct numerical setup for calculating the
atomic mass of Si. [1]
56 A scientist calculated the percent natural abundance of Si-30 in a sample to be 3.29%.
Determine the percent error for this value. [1]
P.S./Chem.–Aug. ’07
[8]
Base your answers to questions 57 through 60 on the information below.
The temperature of a sample of a substance is increased from 20.°C to 160.°C as the
sample absorbs heat at a constant rate of 15 kilojoules per minute at standard pressure. The
graph below represents the relationship between temperature and time as the sample is
heated.
Temperature (°C)
Temperature Versus Time
180.
160.
140.
120.
100.
80.
60.
40.
20.
0
2.0
4.0
6.0
8.0
10.0
12.0
Time (min)
57 What is the boiling point of this sample? [1]
58 In your answer booklet, use the key to draw at least nine particles in the box, showing the
correct particle arrangement of this sample during the first minute of heating. [1]
59 What is the total time this sample is in the liquid phase, only? [1]
60 Determine the total amount of heat required to completely melt this sample at its
melting point. [1]
Base your answers to questions 61 through 63 on the reaction represented by the balanced equation below.
2H2(g) + O2(g) → 2H2O(ᐉ) + 571.6 kJ
61 Identify the information in this equation that indicates the reaction is exothermic. [1]
62 On the axes in your answer booklet, draw a potential energy diagram for the reaction
represented by this equation. [1]
63 Explain why the entropy of the system decreases as the reaction proceeds. [1]
P.S./Chem.–Aug. ’07
[9]
[OVER]
Base your answers to questions 64 through 66 on the information below.
The incomplete equation below represents an esterification reaction. The alcohol
reactant is represented by X.
H O
H C C OH +
H
X
catalyst
H
H O
H
H H
C C O
C
C C H + H2O
H
H
H H
64 On the structural formula in your answer booklet, circle the acid functional group, only.
[1]
65 Write an IUPAC name for the reactant represented by its structural formula in this
equation. [1]
66 In the space in your answer booklet, draw the structural formula for the alcohol represented by X. [1]
P.S./Chem.–Aug. ’07
[10]
Part C
Answer all questions in this part.
Directions (67–84): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 67 through 69 on the information below.
Elements with atomic numbers 112 and 114 have been produced and their IUPAC
names are pending approval. However, an element that would be put between these two
elements on the Periodic Table has not yet been produced. If produced, this element will
be identified by the symbol Uut until an IUPAC name is approved.
67 In the space in your answer booklet, draw a Lewis electron-dot diagram for an atom of
Uut. [1]
68 Determine the charge of an Uut nucleus. Your response must include both the
numerical value and the sign of the charge. [1]
69 Identify one element that would be chemically similar to Uut. [1]
Base your answers to questions 70 through 72 on the information below.
Rust on an automobile door contains Fe2O3(s). The balanced equation representing
one of the reactions between iron in the door of the automobile and oxygen in the atmosphere is given below.
4Fe(s) + 3O2(g) → 2Fe2O3(s)
70 Identify the type of chemical reaction represented by this equation. [1]
71 Determine the gram-formula mass of the product of this reaction. [1]
72 Write the IUPAC name for Fe2O3. [1]
P.S./Chem.–Aug. ’07
[11]
[OVER]
Base your answers to questions 73 through 75 on the information below.
A hydrate is a compound that has water molecules within its crystal structure. The
formula for the hydrate CuSO4•5H2O(s) shows that there are five moles of water for every
one mole of CuSO4(s). When CuSO4•5H2O(s) is heated, the water within the crystals is
released, as represented by the balanced equation below.
CuSO4•5H2O(s) → CuSO4(s) + 5H2O(g)
A student first masses an empty crucible (a heat-resistant container). The student then
masses the crucible containing a sample of CuSO4•5H2O(s). The student repeatedly heats
and masses the crucible and its contents until the mass is constant. The student’s recorded
experimental data and calculations are shown below.
Data and calculation before heating:
mass of CuSO4•5H2O(s) and crucible
– mass of crucible
mass of CuSO4•5H2O(s)
21.37 g
19.24 g
2.13 g
Data and calculation after heating to a constant mass:
mass of CuSO4(s) and crucible
– mass of crucible
20.61 g
19.24 g
mass of CuSO4(s)
1.37 g
Calculation to determine the mass of water:
mass of CuSO4•5H2O(s)
– mass of CuSO4(s)
2.13 g
1.37 g
mass of H2O(g)
0.76 g
73 Identify the total number of significant figures recorded in the calculated mass of
CuSO4•5H2O(s). [1]
74 In the space in your answer booklet, use the student’s data to show a correct numerical
setup for calculating the percent composition by mass of water in the hydrate. [1]
75 Explain why the sample in the crucible must be heated until the constant mass is
reached. [1]
P.S./Chem.–Aug. ’07
[12]
Base your answers to questions 76 and 77 on the information below.
The equilibrium equation below is related to the manufacture of a bleaching solution.
In this equation, Cl–(aq) means that chloride ions are surrounded by water molecules.
Cl2(g) + 2OH–(aq)
OCl–(aq) + Cl–(aq) + H2O(ᐉ)
76 In your answer booklet, use the key to draw two water molecules in the box, showing
the correct orientation of each water molecule toward the chloride ion. [1]
77 Explain, in terms of collision theory, why increasing the concentration of Cl2(g)
increases the concentration of OCl–(aq) in this equilibrium system. [1]
Base your answers to questions 78 through 80 on the information below.
In a laboratory activity, 0.500 mole of NaOH(s) is completely dissolved in distilled water
to form 400. milliliters of NaOH(aq). This solution is then used to titrate a solution of
HNO3(aq).
78 Identify the negative ion produced when the NaOH(s) is dissolved in distilled water. [1]
79 In the space in your answer booklet, calculate the molarity of the NaOH(aq). Your
response must include both a correct numerical setup and the calculated result. [2]
80 In your answer booklet, complete the equation representing this titration reaction by
writing the formulas of the products. [1]
Base your answers to questions 81 and 82 on the information below.
The fossilized remains of a plant were found at a construction site. The fossilized
remains contain
1
16
the amount of carbon-14 that is present in a living plant.
81 Determine the approximate age of these fossilized remains. [1]
82 Complete the nuclear equation in your answer booklet for the decay of C-14. Your
response must include the atomic number, the mass number, and the symbol of the
missing particle. [1]
P.S./Chem.–Aug. ’07
[13]
[OVER]
Base your answers to questions 83 and 84 on the information below.
Electroplating is an electrolytic process used to coat metal objects with a more expensive
and less reactive metal. The diagram below shows an electroplating cell that includes a
battery connected to a silver bar and a metal spoon. The bar and spoon are submerged in
AgNO3(aq).
An Electroplating Cell
+
Battery
–
Wire
Metal spoon
Ag(s)
AgNO3(aq)
83 Explain why AgNO3 is a better choice than AgCl for use in this electrolytic process. [1]
84 Explain the purpose of the battery in this cell. [1]
P.S./Chem.–Aug. ’07
[14]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Thursday, August 16, 2007 — 12:30 to 3:30 p.m., only
ANSWER SHEET
I Male I Female Grade
Student
..............................................
Sex:
...........
Teacher
..............................................
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Thursday, January 24, 2008 — 1:15 to 4:15 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
The use of any communications device is strictly prohibited when taking this
examination. If you use any communications device, no matter how briefly, your
examination will be invalidated and no score will be calculated for you.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
7 Which statement describes a chemical property
of hydrogen gas?
(1) Hydrogen gas burns in air.
(2) Hydrogen gas is colorless.
(3) Hydrogen gas has a density of 0.000 09 g/cm3
at STP.
(4) Hydrogen gas has a boiling point of 20. K at
standard pressure.
1 Which quantity identifies an element?
(1) atomic number
(2) mass number
(3) total number of neutrons in an atom of the
element
(4) total number of valence electrons in an atom
of the element
2 Which atom in the ground state has a partially
filled second electron shell?
(1) hydrogen atom
(3) potassium atom
(2) lithium atom
(4) sodium atom
8 Which element has the greatest density at STP?
(1) calcium
(3) chlorine
(2) carbon
(4) copper
3 What is the total charge of the nucleus of a
nitrogen atom?
(1) +5
(3) +7
(2) +2
(4) +14
9 Which equation shows conservation of atoms?
(1)
(2)
(3)
(4)
4 Which value of an element is calculated using
both the mass and the relative abundance of
each of the naturally occurring isotopes of this
element?
(1) atomic number
(3) half-life
(2) atomic mass
(4) molar volume
10 Which term indicates how strongly an atom
attracts the electrons in a chemical bond?
(1) alkalinity
(2) atomic mass
(3) electronegativity
(4) activation energy
5 The mass of 12 protons is approximately equal to
(1) 1 atomic mass unit
(2) 12 atomic mass units
(3) the mass of 1 electron
(4) the mass of 12 electrons
11 A solid substance is an excellent conductor of
electricity. The chemical bonds in this substance are most likely
(1) ionic, because the valence electrons are
shared between atoms
(2) ionic, because the valence electrons are
mobile
(3) metallic, because the valence electrons are
stationary
(4) metallic, because the valence electrons are
mobile
6 Sodium atoms, potassium atoms, and cesium
atoms have the same
(1) atomic radius
(2) first ionization energy
(3) total number of protons
(4) oxidation state
P.S./Chem.–Jan. ’08
H2 + O2 → H2O
H2 + O2 → 2H2O
2H2 + O2 → 2H2O
2H2 + 2O2 → 2H2O
[2]
19 Which formula represents an alkene?
(1) C2H6
(3) C4H10
(2) C3H6
(4) C5H12
12 Magnesium nitrate contains chemical bonds
that are
(1) covalent, only
(2) ionic, only
(3) both covalent and ionic
(4) neither covalent nor ionic
20 Which term refers to the difference between
the potential energy of the products and the
potential energy of the reactants for any chemical change?
(1) heat of deposition (3) heat of reaction
(2) heat of fusion
(4) heat of vaporization
13 Which substance can be broken down by a
chemical change?
(1) antimony
(3) hexane
(2) carbon
(4) sulfur
21 Which energy conversion occurs in a voltaic
cell?
(1) chemical energy to electrical energy
(2) chemical energy to nuclear energy
(3) electrical energy to chemical energy
(4) nuclear energy to electrical energy
14 Which barium salt is insoluble in water?
(1) BaCO3
(3) Ba(ClO4)2
(2) BaCl2
(4) Ba(NO3)2
15 Which unit can be used to express solution
concentration?
(1) J/mol
(3) mol/L
(2) L /mol
(4) mol/s
22 Which metal is more active than Ni and less
active than Zn?
(1) Cu
(3) Mg
(2) Cr
(4) Pb
16 Under which conditions of temperature and
pressure is a gas most soluble in water?
(1) high temperature and low pressure
(2) high temperature and high pressure
(3) low temperature and low pressure
(4) low temperature and high pressure
23 As water is added to a 0.10 M NaCl aqueous
solution, the conductivity of the resulting
solution
(1) decreases because the concentration of ions
decreases
(2) decreases, but the concentration of ions
remains the same
(3) increases because the concentration of ions
decreases
(4) increases, but the concentration of ions
remains the same
17 Given the equation representing a system at
equilibrium:
H2O(s) H2O(ᐉ)
At which temperature does this equilibrium
exist at 101.3 kilopascals?
(1) 0 K
(3) 32 K
(2) 0°C
(4) 273°C
24 Which substance is an Arrhenius acid?
(1) Ba(OH)2
(3) H3PO4
(2) CH3COOCH3
(4) NaCl
18 In a redox reaction, the total number of
electrons lost is
(1) less than the total number of electrons
gained
(2) greater than the total number of electrons
gained
(3) equal to the total number of electrons
gained
(4) equal to the total number of protons gained
P.S./Chem.–Jan. ’08
25 Which compound releases hydroxide ions in an
aqueous solution?
(3) HCl
(1) CH3COOH
(2) CH3OH
(4) KOH
[3]
[OVER]
29 Which list of nuclear emissions is arranged in
order from the least penetrating power to the
greatest penetrating power?
(1) alpha particle, beta particle, gamma ray
(2) alpha particle, gamma ray, beta particle
(3) gamma ray, beta particle, alpha particle
(4) beta particle, alpha particle, gamma ray
26 Which reaction converts an atom of one
element to an atom of another element?
(1) combustion
(3) saponification
(2) polymerization
(4) transmutation
27 Which nuclear emission has the greatest mass?
(1) alpha particle
(3) gamma ray
(2) beta particle
(4) positron
30 One benefit of nuclear fission reactions is
(1) nuclear reactor meltdowns
(2) storage of waste materials
(3) biological exposure
(4) production of energy
28 Which two radioisotopes have the same decay
mode?
(3) 37K and 42K
(1) 37Ca and 53Fe
(2) 220Fr and 60Co
(4) 99 Tc and 19Ne
P.S./Chem.–Jan. ’08
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
31 Which list of elements consists of metalloids,
only?
(1) B, Al, Ga
(3) O, S, Se
(2) C, N, P
(4) Si, Ge, As
37 In which compound is the ratio of metal ions to
nonmetal ions 1 to 2?
(1) calcium bromide
(3) calcium phosphide
(2) calcium oxide
(4) calcium sulfide
32 Which two notations represent different
isotopes of the same element?
38 What is the concentration of O2(g), in parts per
million, in a solution that contains 0.008 gram of
O2(g) dissolved in 1000. grams of H2O(ᐉ)?
(1) 0.8 ppm
(3) 80 ppm
(2) 8 ppm
(4) 800 ppm
(1) 64Be and 94 Be
(3)
14 N
7
and 146 C
(2) 73 Li and 73 Li
(4)
32 P
15
and 32
16 S
33 Which general trend is found in Period 2 on the
Periodic Table as the elements are considered in
order of increasing atomic number?
(1) decreasing atomic mass
(2) decreasing electronegativity
(3) increasing atomic radius
(4) increasing first ionization energy
39 The table below shows data for the temperature,
pressure, and volume of four gas samples.
Data for Four Gas Samples
Gas
Temperature Pressure
Sample
(K)
(atm)
34 What is the gram-formula mass of Ca3(PO4)2?
(1) 248 g/mol
(3) 279 g/mol
(2) 263 g/mol
(4) 310. g/mol
35 What is the total number of pairs of electrons
shared between the carbon atom and the oxygen
atom in a molecule of methanal?
(1) 1
(3) 3
(2) 2
(4) 4
A
100.
2
400.
B
200.
2
200.
C
100.
2
400.
D
200.
4
200.
Which two gas samples have the same total
number of molecules?
(1) A and B
(3) B and C
(2) A and C
(4) B and D
40 At which temperature is the vapor pressure of
ethanol equal to the vapor pressure of
propanone at 35°C?
(1) 35°C
(3) 82°C
(2) 60.°C
(4) 95°C
36 When sodium and fluorine combine to produce
the compound NaF, the ions formed have the
same electron configuration as atoms of
(1) argon, only
(2) neon, only
(3) both argon and neon
(4) neither argon nor neon
P.S./Chem.–Jan. ’08
Volume
(mL)
[5]
[OVER]
41 A rigid cylinder with a movable piston contains
a 2.0-liter sample of neon gas at STP. What is
the volume of this sample when its temperature
is increased to 30.°C while its pressure is
decreased to 90. kilopascals?
(1) 2.5 L
(3) 1.6 L
(2) 2.0 L
(4) 0.22 L
46 Which volume of 0.10 M NaOH(aq) exactly
neutralizes 15.0 milliliters of 0.20 M HNO3(aq)?
(1) 1.5 mL
(3) 3.0 mL
(2) 7.5 mL
(4) 30. mL
47 Which indicator, when added to a solution,
changes color from yellow to blue as the pH of
the solution is changed from 5.5 to 8.0?
(1) bromcresol green
(3) litmus
(2) bromthymol blue
(4) methyl orange
42 Which compound is a saturated hydrocarbon?
(1) CH2CH2
(3) CH3CHO
(2) CH3CH3
(4) CH3CH2OH
48 The pH of an aqueous solution changes from
4 to 3 when the hydrogen ion concentration in
the solution is
43 A molecule of a compound contains a total of
10 hydrogen atoms and has the general formula
CnH2n+2. Which prefix is used in the name of
this compound?
(1) but(3) oct(2) dec(4) pent-
(1) decreased by a factor of
3
4
(2) decreased by a factor of 10
(3) increased by a factor of
4
3
(4) increased by a factor of 10
44 Reduction occurs at the cathode in
(1) electrolytic cells, only
(2) voltaic cells, only
(3) both electrolytic cells and voltaic cells
(4) neither electrolytic cells nor voltaic cells
49 Which fraction of an original 20.00-gram
sample of nitrogen-16 remains unchanged after
36.0 seconds?
45 What are the products of a reaction between
KOH(aq) and HCl(aq)?
(1) H2 and KClO
(3) KH and HClO
(2) H2O and KCl
(4) KOH and HCl
P.S./Chem.–Jan. ’08
(1)
1
5
(3)
1
16
(2)
1
8
(4)
1
32
50 Which radioactive isotope is used in treating
cancer?
(1) carbon-14
(3) lead-206
(2) cobalt-60
(4) uranium-238
[6]
Part B–2
Answer all questions in this part.
Directions (51–65): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
51 Describe one chemical property of Group 1 metals that results from the atoms of each
metal having only one valence electron. [1]
52 Given the balanced equation representing a reaction:
N2(g) + O2(g) + 182.6 kJ → 2NO(g)
On the labeled axes in your answer booklet, draw a potential energy diagram for this
reaction. [1]
53 Write one electron configuration for an atom of silicon in an excited state.
54 Write the empirical formula for the compound C8H18.
P.S./Chem.–Jan. ’08
[7]
[1]
[1]
[OVER]
Base your answers to questions 55 through 57 on the information below.
Atomic Diagrams of Magnesium and Aluminum
Key
= electron
Element
Lewis Electron-Dot
Diagram
magnesium
Mg
Electron-Shell
Diagram
12 p
11 n
Al
aluminum
13 p
14 n
55 Identify one piece of information shown in the electron-shell diagrams that is not shown
in the Lewis electron-dot diagrams. [1]
56 Determine the mass number of the magnesium atom represented by the electron-shell
diagram. [1]
57 Explain why Lewis electron-dot diagrams are generally more suitable than
electron-shell diagrams for illustrating chemical bonding. [1]
P.S./Chem.–Jan. ’08
[8]
Base your answers to questions 58 through 60 on the information below.
A 100.0-gram sample of NaCl(s) has an initial temperature of 0°C. A chemist measures
the temperature of the sample as it is heated. Heat is not added at a constant rate. The
heating curve for the sample is shown below.
Heating Curve for Sodium Chloride
D
Temperature (°C)
1465
B
801
0
E
C
A
Time
58 Determine the temperature range over which the entire NaCl sample is a liquid.
[1]
59 Identify one line segment on the curve where the average kinetic energy of the
particles of the NaCl sample is changing. [1]
60 Identify one line segment on the curve where the NaCl sample is in a single phase and
capable of conducting electricity. [1]
Base your answers to questions 61 through 63 on the information below.
A beaker contains 100.0 milliliters of a dilute aqueous solution of ethanoic acid at
equilibrium. The equation below represents this system.
HC2H3O2 (aq) H+(aq) + C2H3O2 –(aq)
61 Compare the rate of the forward reaction to the rate of the reverse reaction for this
system. [1]
62 Describe what happens to the concentration of H+(aq) when 10 drops of concentrated
HC2H3O2(aq) are added to this system. [1]
63 In the space in your answer booklet, draw a structural formula for ethanoic acid.
P.S./Chem.–Jan. ’08
[9]
[1]
[OVER]
Base your answers to questions 64 and 65 on the information below.
A solution is made by completely dissolving 90. grams of KNO3(s) in 100. grams of
water in a beaker. The temperature of this solution is 65°C.
64 Describe the effect on the solubility of KNO3(s) in this solution when the pressure on
the solution increases. [1]
65 Determine the total mass of KNO3(s) that settles to the bottom of the beaker when the
original solution is cooled to 15°C. [1]
P.S./Chem.–Jan. ’08
[10]
Part C
Answer all questions in this part.
Directions (66–83): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 66 through 68 on the information below.
The compound 1,2-ethanediol can be mixed with water. This mixture is added to
automobile radiators as an engine coolant. The cooling system of a small van contains
6690 grams of 1,2-ethanediol. Some properties of water and 1,2-ethanediol are given in the
table below.
Properties of Water and 1,2-ethanediol
Water
(H2O)
Property
gram-formula mass (g/mol)
boiling point at standard pressure (°C)
1,2-ethanediol
(CH2OHCH2OH)
18.0
62.0
100.0
197.2
66 Identify the class of organic compounds to which 1,2-ethanediol belongs.
[1]
67 State, in terms of molecular polarity, why 1,2-ethanediol is soluble in water.
[1]
68 In the space in your answer booklet, calculate the total number of moles of 1, 2-ethanediol
in the small van’s cooling system. Your response must include both a correct
numerical setup and the calculated result. [2]
Base your answers to questions 69 through 71 on the information below.
“Hand Blasters” is a toy that consists of a set of two ceramic balls, each coated with a
mixture of sulfur and potassium chlorate, KClO3. When the two balls are struck together,
a loud popping noise is produced as sulfur and potassium chlorate react with each other.
69 Balance the equation in your answer booklet for the “Hand Blaster” reaction, using the
smallest whole-number coefficients. [1]
70 Identify one source of the activation energy for this reaction.
[1]
71 Determine the oxidation number of chlorine in the reactant that contains chlorine.
P.S./Chem.–Jan. ’08
[11]
[1]
[OVER]
Base your answers to questions 72 through 74 on the information below.
A laboratory worker filled a bottle with a hydrochloric acid solution. Another bottle was
filled with methanol, while a third bottle was filled with a sodium hydroxide solution.
However, the worker neglected to label each bottle. After a few days, the worker could not
remember which liquid was in each bottle.
The worker needed to identify the liquid in each bottle. The bottles were labeled A, B,
and C. Using materials found in the lab (indicators, conductivity apparatus, and pieces of
Mg metal), the worker tested samples of liquid from each bottle. The test results are shown
in the table below.
Table of Tests and Results
Test
Test Results
Bottle A
Bottle B
Bottle C
methyl orange indicator
yellow
yellow
yellow
bromthymol blue indicator
blue
green
yellow
electrical conductivity
conductor
nonconductor
conductor
reactivity with Mg metal
no reaction
no reaction
reaction
72 Using the test results, state how the worker differentiated the bottle that contained
methanol from the other two bottles. [1]
73 The worker concluded that bottle C contained hydrochloric acid. Identify one test and
state the corresponding test result that supports this conclusion. [1]
74 Explain, in terms of pH, why the methyl orange indicator test results were the same for
each of the three liquids. [1]
P.S./Chem.–Jan. ’08
[12]
Base your answers to questions 75 and 76 on the information below.
A student performed an experiment to determine the total amount of energy stored in
a peanut. The accepted value for the energy content of a peanut is 30.2 kilojoules per gram.
The student measured 100.0 grams of water into a metal can and placed the can on a
ring stand, as shown in the diagram below. The peanut was attached to a wire suspended
under the can. The initial temperature of the water was recorded as 22.0°C. The peanut
was ignited and allowed to burn. When the peanut finished burning, the final water
temperature was recorded as 57.0°C. The student’s experimental value for the energy
content of this peanut was 25.9 kilojoules per gram.
Thermometer
Metal can
100.0 g
H2O( )
Peanut
75 In the space in your answer booklet, calculate the total amount of heat absorbed by the
water. Your response must include both a correct numerical setup and the calculated
result. [2]
76 Determine the student’s percent error for the energy content of this peanut.
[1]
Base your answers to questions 77 through 79 on the information below.
Some dry chemicals can be used to put out forest fires. One of these chemicals is
NaHCO3. When NaHCO3(s) is heated, one of the products is CO2(g), as shown in the
balanced equation below.
2NaHCO3(s) + heat → Na2CO3(s) + H2O(g) + CO2 (g)
77 In the space in your answer booklet, show a correct numerical setup for calculating the
percent composition by mass of carbon in the product Na2CO3. [1]
78 Identify the type of chemical reaction represented by this equation.
[1]
79 Determine the total number of moles of CO2(g) produced when 7.0 moles of
NaHCO3(s) is completely reacted. [1]
P.S./Chem.–Jan. ’08
[13]
[OVER]
Base your answers to questions 80 and 81 on the information below.
In an investigation, a dripless wax candle is massed and then lighted. As the candle
burns, a small amount of liquid wax forms near the flame. After 10 minutes, the candle’s
flame is extinguished and the candle is allowed to cool. The cooled candle is massed.
80 Identify one physical change that takes place in this investigation.
[1]
81 State one observation that indicates a chemical change has occurred in this
investigation. [1]
Base your answers to questions 82 and 83 on the information below.
The graph below shows the relationship between boiling point and molar mass at
standard pressure for pentane, hexane, heptane, and nonane.
Boiling Point Versus Molar Mass of Some Alkanes
160.
Boiling Point (°C)
140.
120.
100.
80.
60.
40.
20.
70.
80.
90.
100.
110.
120.
Molar Mass (g/mol)
82 Octane has a molar mass of 114 grams per mole. According to this graph, what is the
boiling point of octane at standard pressure? [1]
83 State the relationship between molar mass and the strength of intermolecular forces for
the selected alkanes. [1]
P.S./Chem.–Jan. ’08
[14]
130.
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Thursday, January 24, 2008 — 1:15 to 4:15 p.m., only
ANSWER SHEET
I Male I Female Grade . . . . . . . . . . . .
Student . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sex:
Teacher . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Tuesday, June 17, 2008 — 1:15 to 4:15 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
The use of any communications device is strictly prohibited when taking this
examination. If you use any communications device, no matter how briefly, your
examination will be invalidated and no score will be calculated for you.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
7 Given the balanced equation representing a
reaction:
1 An atom in the ground state has seven valence
electrons. This atom could be an atom of which
element?
(1) calcium
(3) oxygen
(2) fluorine
(4) sodium
H+(aq) + OH–(aq) → H2O(ᐉ) + energy
In this reaction there is conservation of
(1) mass, only
(2) mass and charge, only
(3) charge and energy, only
(4) charge, energy, and mass
2 What is the total number of electrons in an atom
of potassium?
(1) 18
(3) 20
(2) 19
(4) 39
8 Which statement describes the composition of
potassium chlorate, KClO3?
(1) The proportion by mass of elements
combined in potassium chlorate is fixed.
(2) The proportion by mass of elements
combined in potassium chlorate varies.
(3) Potassium chlorate is composed of four
elements.
(4) Potassium chlorate is composed of five
elements.
3 A proton has a charge that is opposite the charge
of
(1) an alpha particle
(3) an electron
(2) a neutron
(4) a positron
4 Which conclusion was a direct result of the gold
foil experiment?
(1) An atom is mostly empty space with a dense,
positively charged nucleus.
(2) An atom is composed of at least three types
of subatomic particles.
(3) An electron has a positive charge and is
located inside the nucleus.
(4) An electron has properties of both waves
and particles.
9 As a bond between a hydrogen atom and a
sulfur atom is formed, electrons are
(1) shared to form an ionic bond
(2) shared to form a covalent bond
(3) transferred to form an ionic bond
(4) transferred to form a covalent bond
5 Which statement identifies the element arsenic?
(1) Arsenic has an atomic number of 33.
(2) Arsenic has a melting point of 84 K.
(3) An atom of arsenic in the ground state has
eight valence electrons.
(4) An atom of arsenic in the ground state has a
radius of 146 pm.
10 Atoms of which element can bond to each other
to form chains, rings, and networks?
(1) carbon
(3) hydrogen
(2) fluorine
(4) oxygen
11 Which formula represents a polar molecule?
(1) Br2
(3) CH4
6 Which element has an atom with the greatest
attraction for electrons in a chemical bond?
(1) As
(3) N
(2) Bi
(4) P
P.S./Chem.–June ’08
(2) CO2
[2]
(4) NH3
18 Which process increases the potential energy of
the particles of a sample?
(1) condensation
(3) solidification
(2) deposition
(4) vaporization
12 Two solid samples each contain sulfur, oxygen,
and sodium, only. These samples have the same
color, melting point, density, and reaction with
an aqueous barium chloride solution. It can be
concluded that the two samples are the same
(1) compound
(3) mixture
(2) element
(4) solution
19 Which sample at STP has the same number of
molecules as 5 liters of NO2(g) at STP?
(1) 5 grams of H2(g)
(2) 5 liters of CH4(g)
(3) 5 moles of O2(g)
(4) 5 × 1023 molecules of CO2(g)
13 Which equation represents a physical change?
(1) H2O(s) + 6.01 kJ → H2O(ᐉ)
(2) 2H2(g) + O2(g) → 2H2O(g) + 483.6 kJ
(3) H2(g) + I2(g) + 53.0 kJ → 2HI(g)
(4) N2(g) + 2O2(g) + 66.4 kJ → 2NO2(g)
20 Under which conditions of temperature and
pressure does oxygen gas behave least like an
ideal gas?
(1) low temperature and low pressure
(2) low temperature and high pressure
(3) high temperature and low pressure
(4) high temperature and high pressure
14 Which liquid has the lowest vapor pressure at
65°C?
(1) ethanoic acid
(3) propanone
(2) ethanol
(4) water
15 Which substance can not be broken down by a
chemical reaction?
(1) ammonia
(3) methane
(2) argon
(4) water
21 How is a chemical reaction affected by the
addition of a catalyst?
(1) The activation energy decreases.
(2) The heat of reaction increases.
(3) The number of collisions between particles
decreases.
(4) The potential energy of the reactants
increases.
16 In which sample is the average kinetic energy of
the particles greatest?
(1) 10. mL of HCl(aq) at 25°C
(2) 15 mL of HCl(aq) at 20.°C
(3) 10. mL of H2O(ᐉ) at 35°C
(4) 15 mL of H2O(ᐉ) at 30.°C
22 Systems in nature tend to undergo changes
toward
(1) lower energy and less disorder
(2) lower energy and more disorder
(3) higher energy and less disorder
(4) higher energy and more disorder
17 A thermometer is in a beaker of water. Which
statement best explains why the thermometer
reading initially increases when LiBr(s) is
dissolved in the water?
(1) The entropy of the LiBr(aq) is greater than
the entropy of the water.
(2) The entropy of the LiBr(aq) is less than the
entropy of the water.
(3) The dissolving of the LiBr(s) in water is an
endothermic process.
(4) The dissolving of the LiBr(s) in water is an
exothermic process.
P.S./Chem.–June ’08
23 What can be concluded if an ion of an element
is smaller than an atom of the same element?
(1) The ion is negatively charged because it has
fewer electrons than the atom.
(2) The ion is negatively charged because it has
more electrons than the atom.
(3) The ion is positively charged because it has
fewer electrons than the atom.
(4) The ion is positively charged because it has
more electrons than the atom.
[3]
[OVER]
28 Which type of reaction occurs when a highenergy particle collides with the nucleus of an
atom, converting that atom to an atom of a
different element?
(1) addition
(3) substitution
(2) neutralization
(4) transmutation
24 Which class of organic compounds has molecules
that contain nitrogen atoms?
(1) alcohol
(3) ether
(2) amine
(4) ketone
25 Which two compounds have the same molecular
formula but different chemical and physical
properties?
(1) CH3CH2Cl and CH3CH2Br
(2) CH3CHCH2 and CH3CH2CH3
(3) CH3CHO and CH3COCH3
(4) CH3CH2OH and CH3OCH3
29 Which particle is emitted when an atom of 85Kr
spontaneously decays?
(1) an alpha particle
(3) a neutron
(2) a beta particle
(4) a proton
30 What is a problem commonly associated with
nuclear power facilities?
(1) A small quantity of energy is produced.
(2) Reaction products contribute to acid rain.
(3) It is impossible to control nuclear fission.
(4) It is difficult to dispose of wastes.
26 Which half-reaction equation represents the
reduction of a potassium ion?
(3) K+ → K + e–
(1) K+ + e– → K
(2) K + e– → K+
(4) K → K+ + e–
27 According to the Arrhenius theory, an acid is a
substance that
(1) changes litmus from red to blue
(2) changes phenolphthalein from colorless to
pink
(3) produces hydronium ions as the only positive
ions in an aqueous solution
(4) produces hydroxide ions as the only negative
ions in an aqueous solution
P.S./Chem.–June ’08
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
31 The wave-mechanical model of the atom is
required to explain the
(1) mass number and atomic number of an
atom
(2) organization of atoms in a crystal
(3) radioactive nature of some atoms
(4) spectra of elements with multielectron
atoms
35 A student measures the mass and volume of a
piece of aluminum. The measurements are
25.6 grams and 9.1 cubic centimeters. The
student calculates the density of the aluminum.
What is the percent error of the student’s
calculated density of aluminum?
(1) 1%
(3) 3%
(2) 2%
(4) 4%
32 Magnesium and calcium have similar chemical
properties because an atom of each element has
the same total number of
(1) electron shells
(3) neutrons
(2) valence electrons
(4) protons
36 Given the balanced equation representing a
reaction:
2H2 + O2 → 2H2O
What is the total mass of water formed when
8 grams of hydrogen reacts completely with
64 grams of oxygen?
33 The diagram below represents the nucleus of an
atom.
(1) 18 g
(2) 36 g
(3) 56 g
(4) 72 g
Key
37 Which compound contains both ionic and
covalent bonds?
(1) ammonia
(2) methane
(3) sodium nitrate
(4) potassium chloride
= proton
= neutron
What are the atomic number and mass number
of this atom?
(1) The atomic number
number is 19.
(2) The atomic number
number is 20.
(3) The atomic number
number is 19.
(4) The atomic number
number is 20.
is 9 and the mass
38 An iron bar at 325 K is placed in a sample of
water. The iron bar gains energy from the water
if the temperature of the water is
(1) 65 K
(3) 65°C
(2) 45 K
(4) 45°C
is 9 and the mass
is 11 and the mass
is 11 and the mass
34 A barium atom attains a stable electron
configuration when it bonds with
(1) one chlorine atom
(2) two chlorine atoms
(3) one sodium atom
(4) two sodium atoms
P.S./Chem.–June ’08
[5]
[OVER]
42 Given the balanced equation representing a
reaction:
39 Which particle model diagram represents only
one compound composed of elements X and Z?
C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(g)
Key
= atom of element X
= atom of element Z
What is the total number of moles of O2(g)
required for the complete combustion of
1.5 moles of C3H8(g)?
(1) 0.30 mol
(2) 1.5 mol
(1)
(2)
43 A sample of gas occupies a volume of 50.0 milliliters in a cylinder with a movable piston. The
pressure of the sample is 0.90 atmosphere and
the temperature is 298 K. What is the volume of
the sample at STP?
(1) 41 mL
(3) 51 mL
(2) 49 mL
(4) 55 mL
(3)
44 Which solution has the lowest freezing point?
(1) 10. g of KI dissolved in 100. g of water
(2) 20. g of KI dissolved in 200. g of water
(3) 30. g of KI dissolved in 100. g of water
(4) 40. g of KI dissolved in 200. g of water
(4)
40 Given the balanced equation representing a
reaction:
45 Which 1-mole sample has the least entropy?
(1) Br2(s) at 266 K
(3) Br2(ᐉ) at 332 K
(2) Br2(ᐉ) at 266 K
(4) Br2(g) at 332 K
Cu + S → CuS + energy
Which statement explains why the energy term
is written to the right of the arrow?
46 At 20.°C, a 1.2-gram sample of Mg ribbon reacts
rapidly with 10.0 milliliters of 1.0 M HCl(aq).
Which change in conditions would have caused
the reaction to proceed more slowly?
(1) increasing the initial temperature to 25°C
(2) decreasing the concentration of HCl(aq) to
0.1 M
(3) using 1.2 g of powdered Mg
(4) using 2.4 g of Mg ribbon
(1) The compound CuS is composed of two
metals.
(2) The compound CuS is composed of two
nonmetals.
(3) Energy is absorbed as the bonds in CuS
form.
(4) Energy is released as the bonds in CuS form.
41 A 1.0-gram sample of which element will uniformly fill a closed 2.0-liter container at STP?
(1) antimony
(3) tellurium
(2) sulfur
(4) xenon
P.S./Chem.–June ’08
(3) 4.5 mol
(4) 7.5 mol
47 Which general formula represents the compound
CH3CH2CCH?
(3) CnH2n–2
(1) CnHn
(2) CnH2n
(4) CnH2n+2
[6]
50 An original sample of K-40 has a mass of
25.00 grams. After 3.9 × 109 years, 3.125 grams
of the original sample remains unchanged. What
is the half-life of K-40?
(1) 1.3 × 109 y
(3) 3.9 × 109 y
(2) 2.6 × 109 y
(4) 1.2 × 1010 y
48 Which compound dissolves in water to form an
aqueous solution that can conduct an electric
current?
(1) CCl4
(3) CH3COOH
(2) C2H5OH
(4) CH4
49 Given the equation representing a reaction at
equilibrium:
NH3(g) + H2O(ᐉ) NH4+(aq) + OH–(aq)
The H+ acceptor for the forward reaction is
(1) H2O(ᐉ)
(2) NH3(g)
P.S./Chem.–June ’08
(3) NH4+(aq)
(4) OH–(aq)
[7]
[OVER]
Part B–2
Answer all questions in this part.
Directions (51–64): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 51 and 52 on the information below.
In a titration, 15.65 milliliters of a KOH(aq) solution exactly neutralized 10.00 milliliters
of a 1.22 M HCl(aq) solution.
51 Complete the equation in your answer booklet for the titration reaction by writing the
formula of each product. [1]
52 In the space in your answer booklet, show a correct numerical setup for calculating the
molarity of the KOH(aq) solution. [1]
Base your answers to questions 53 through 55 on the information below.
A 150.-gram liquid sample of stearic acid, C17H35COOH, is cooled at a constant rate.
The temperature of the sample is recorded at 2-minute intervals in the data table below.
Cooling Data for Stearic Acid
Time (min) Temperature (°C)
0
75.0
2
72.0
4
69.3
6
69.3
8
69.3
10.
69.3
12
65.0
53 Identify the physical change occurring during the time interval 4 minutes to
10. minutes. [1]
54 On the grid in your answer booklet:
• Mark an appropriate scale on the axis labeled “Temperature (°C).” [1]
• Plot the data from the data table. Circle and connect the points. [1]
55 Determine the gram-formula mass of stearic acid. [1]
P.S./Chem.–June ’08
[8]
Base your answers to questions 56 through 58 on the information below.
An unsaturated solution is made by completely dissolving 20.0 grams of NaNO3 in
100.0 grams of water at 20.0°C.
56 In the space in your answer booklet, show a correct numerical setup for calculating the
number of moles of NaNO3 (gram-formula mass = 85.0 grams per mole) used to make
this unsaturated solution. [1]
57 Determine the minimum mass of NaNO3 that must be added to this unsaturated
solution to make a saturated solution at 20.0°C. [1]
58 Identify one process that can be used to recover the NaNO3 from the unsaturated
solution. [1]
Base your answers to questions 59 through 61 on the information below.
The hydrocarbon 2-methylpropane reacts with iodine as represented by the balanced
equation below. At standard pressure, the boiling point of 2-methylpropane is lower than
the boiling point of 2-iodo-2-methylpropane.
H
H
C
H
H
H
H
H
H
H
C
C
C
H
H
H
H
2-methylpropane
I
I
H
C
H
H
C
C
C
H
I
H
H
H
I
2-iodo-2-methylpropane
59 To which class of organic compounds does this organic product belong? [1]
60 Explain, in terms of bonding, why the hydrocarbon 2-methylpropane is saturated. [1]
61 Explain the difference in the boiling points of 2-methylpropane and
2-iodo-2-methylpropane in terms of both molecular polarity and intermolecular
forces. [2]
P.S./Chem.–June ’08
[9]
[OVER]
Base your answers to questions 62 through 64 on the information below.
Nitrogen gas, hydrogen gas, and ammonia gas are in equilibrium in a closed container
at constant temperature and pressure. The equation below represents this equilibrium.
N2(g) + 3H2(g) 2NH3(g)
The graph below shows the initial concentration of each gas, the changes that occur as
a result of adding H2(g) to the system, and the final concentrations when equilibrium is
reestablished.
Concentration of Reaction Gases Versus Time
H2 added
at this time
Initial
Final
Concentration
H2
NH3
N2
Time
62 What information on the graph indicates that the system was initially at equilibrium? [1]
63 Explain, in terms of LeChatelier’s principle, why the final concentration of NH3(g) is
greater than the initial concentration of NH3(g). [1]
64 Explain, in terms of collision theory, why the concentration of H2(g) begins to decrease
immediately after more H2(g) is added to the system. [1]
P.S./Chem.–June ’08
[10]
Part C
Answer all questions in this part.
Directions (65–79): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 65 through 67 on the information below.
An unlit candle is secured to the bottom of a 200-milliliter glass beaker. Baking soda
(sodium hydrogen carbonate) is added around the base of the candle as shown below.
Candle
Baking soda
The candle is lit and dilute ethanoic acid is poured down the inside of the beaker. As
the acid reacts with the baking soda, bubbles of CO2 gas form. After a few seconds, the air
in the beaker is replaced by 0.20 liter of CO2 gas, causing the candle flame to go out. The
density of CO2 gas is 1.8 grams per liter at room temperature.
65 Write the chemical formula for baking soda. [1]
66 In the space in your answer booklet, draw a structural formula for the acid that was
poured into the beaker. [1]
67 Calculate the mass of the CO2 gas that replaced the air in the beaker. Your response
must include both a correct numerical setup and the calculated result. [2]
P.S./Chem.–June ’08
[11]
[OVER]
Base your answers to questions 68 through 71 on the information below.
The health of fish depends on the amount of oxygen dissolved in the water. A dissolved
oxygen (DO) concentration between 6 parts per million and 8 parts per million is best for
fish health. A DO concentration greater than 1 part per million is necessary for fish survival.
Fish health is also affected by water temperature and concentrations of dissolved
ammonia, hydrogen sulfide, chloride compounds, and nitrate compounds. Most freshwater
fish thrive in water with a pH between 6.5 and 8.5.
A student’s fish tank contains fish, green plants, and 3800 grams of fish-tank water with
2.7 × 10–2 gram of dissolved oxygen. Phenolphthalein tests colorless and bromthymol blue
tests blue in samples of the fish-tank water.
68 Based on the test results for the indicators phenolphthalein and bromthymol blue, what
is the pH range of the fish-tank water? [1]
69 When the fish-tank water has a pH of 8.0, the hydronium ion concentration is
1.0 × 10–8 mole per liter. What is the hydronium ion concentration when the water has
a pH of 7.0? [1]
70 State how an increase in the temperature of the fish-tank water affects the solubility of
oxygen in the water. [1]
71 Determine if the DO concentration in the fish tank is healthy for fish. Your response
must include:
• a correct numerical setup to calculate the DO concentration in the water in parts per
million [1]
• the calculated result [1]
• a statement using your calculated result that tells why the DO concentration in the
water is or is not healthy for fish [1]
P.S./Chem.–June ’08
[12]
Base your answers to questions 72 and 73 on the information below.
The Balmer series refers to the visible bright lines in the spectrum produced by hydrogen
atoms. The color and wavelength of each line in this series are given in the table below.
Balmer Series for Hydrogen
Color
Wavelength (nm)
red
656.3
blue green
486.1
blue
434.1
violet
410.2
72 On the diagram in your answer booklet, draw four vertical lines to represent the Balmer
series. [1]
73 Explain, in terms of both subatomic particles and energy states, how the Balmer series
is produced. [1]
Base your answers to questions 74 through 76 on the information below.
A flashlight can be powered by a rechargeable nickel-cadmium battery. In the battery,
the anode is Cd(s) and the cathode is NiO2(s). The unbalanced equation below represents
the reaction that occurs as the battery produces electricity. When a nickel-cadmium battery
is recharged, the reverse reaction occurs.
Cd(s) + NiO2(s) + H2O(ᐉ) → Cd(OH)2(s) + Ni(OH)2(s)
74 Balance the equation in your answer booklet for the reaction that produces electricity,
using the smallest whole-number coefficients. [1]
75 Determine the change in oxidation number for the element that makes up the anode in
the reaction that produces electricity. [1]
76 Explain why Cd would be above Ni if placed on Table J. [1]
P.S./Chem.–June ’08
[13]
[OVER]
Base your answers to questions 77 through 79 on the information below.
A battery-operated smoke detector produces an alarming sound when its electrical
sensor detects smoke particles. Some ionizing smoke detectors contain the radioisotope
americium-241, which undergoes alpha decay and has a half-life of 433 years. The emitted
alpha particles ionize gas molecules in the air. As a result, an electric current flows through
the detector. When smoke particles enter the detector, the flow of ions is interrupted,
causing the alarm to sound.
77 Complete the nuclear equation in your answer booklet for the decay of Am-241. Your
response must include the symbol, mass number, and atomic number for each
product. [2]
78 State one scientific reason why Am-241 is a more appropriate radioactive source than
Fr-220 in an ionizing smoke detector. [1]
79 Explain, in terms of particle behavior, why smoke particles cause the detector alarm to
sound. [1]
P.S./Chem.–June ’08
[14]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Tuesday, June 17, 2008 — 1:15 to 4:15 p.m., only
ANSWER SHEET
I Male I Female Grade . . . . . . . . . . . .
Student . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sex:
Teacher . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Wednesday, August 13, 2008 — 12:30 to 3:30 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
The use of any communications device is strictly prohibited when taking this
examination. If you use any communications device, no matter how briefly, your
examination will be invalidated and no score will be calculated for you.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
6 Chlorine-37 can be represented as
(1) 17
(3) 35
35Cl
20Cl
1 In the wave-mechanical model of the atom,
orbitals are regions of the most probable
locations of
(1) protons
(3) neutrons
(2) positrons
(4) electrons
(2)
(4)
37Cl
17
7 Which element is a metal that is in the liquid
phase at STP?
(1) bromine
(3) hydrogen
(2) cobalt
(4) mercury
2 Which phrase describes an atom?
(1) a positively charged electron cloud surrounding a positively charged nucleus
(2) a positively charged electron cloud surrounding a negatively charged nucleus
(3) a negatively charged electron cloud surrounding a positively charged nucleus
(4) a negatively charged electron cloud surrounding a negatively charged nucleus
8 Which list of formulas represents compounds,
only?
(3) H2, Ne, NaCl
(1) CO2, H2O, NH3
(2) H2, N2, O2
(4) MgO, NaCl, O2
9 What is the chemical formula for iron(III) oxide?
(1) FeO
(3) Fe3O
(2) Fe2O3
(4) Fe3O2
3 Which total mass is the smallest?
(1) the mass of 2 electrons
(2) the mass of 2 neutrons
(3) the mass of 1 electron plus the mass of
1 proton
(4) the mass of 1 neutron plus the mass of
1 electron
10 An atom of which element has the greatest
attraction for the electrons in a bond with a
hydrogen atom?
(1) chlorine
(3) silicon
(2) phosphorus
(4) sulfur
4 Elements on the modern Periodic Table are
arranged in order of increasing
(1) atomic mass
(2) atomic number
(3) number of neutrons
(4) number of valence electrons
11 Which property could be used to identify a
compound in the laboratory?
(1) mass
(3) temperature
(2) melting point
(4) volume
5 As the elements of Group 17 are considered in
order of increasing atomic number, there is an
increase in
(1) atomic radius
(2) electronegativity
(3) first ionization energy
(4) number of electrons in the first shell
P.S./Chem.–Aug. ’08
20Cl
37
12 Which statement describes what occurs as two
atoms of bromine combine to become a
molecule of bromine?
(1) Energy is absorbed as a bond is formed.
(2) Energy is absorbed as a bond is broken.
(3) Energy is released as a bond is formed.
(4) Energy is released as a bond is broken.
[2]
13 Given a formula for oxygen:
19 Hydrocarbons are compounds that contain
(1) carbon, only
(2) carbon and hydrogen, only
(3) carbon, hydrogen, and oxygen, only
(4) carbon, hydrogen, oxygen, and nitrogen, only
O=O
What is the total number of electrons shared
between the atoms represented in this formula?
(1) 1
(2) 2
20 The reaction that joins thousands of small,
identical molecules to form one very long
molecule is called
(1) esterification
(3) polymerization
(2) fermentation
(4) substitution
(3) 8
(4) 4
14 Solid ZnCl2 and liquid ZnCl2 have different
(1) empirical formulas (3) ion ratios
(2) formula masses
(4) physical properties
21 What is the IUPAC name of the organic
compound that has the formula shown below?
15 Which phrase describes the molarity of a
solution?
(1) liters of solute per mole of solution
(2) liters of solution per mole of solution
(3) moles of solute per liter of solution
(4) moles of solution per liter of solution
H
H
H
C C C
H
16 Which substance can not be decomposed by a
chemical change?
(1) AlCl3
(3) HI
(2) H2O
(4) Cu
H
C C
H H
H
H
(1) 1,1-dimethylbutane (3) hexane
(2) 2-methylpentane
(4) 4-methylpentane
22 A voltaic cell spontaneously converts chemical
energy to
(1) electrical energy
(3) mechanical energy
(2) geothermal energy (4) nuclear energy
17 Tetrachloromethane, CCl4, is classified as a
(1) compound because the atoms of the
elements are combined in a fixed proportion
(2) compound because the atoms of the
elements are combined in a proportion that
varies
(3) mixture because the atoms of the elements
are combined in a fixed proportion
(4) mixture because the atoms of the elements
are combined in a proportion that varies
23 Given the balanced equation representing a
reaction:
Mg(s) + Ni2+(aq) → Mg2+(aq) + Ni(s)
What is the total number of moles of electrons
lost by Mg(s) when 2.0 moles of electrons are
gained by Ni2+(aq)?
18 Which formulas represent two polar molecules?
(1) CO2 and HCl
(3) H2O and HCl
(2) CO2 and CH4
(4) H2O and CH4
P.S./Chem.–Aug. ’08
H C H
H H
H
(1) 1.0 mol
(2) 2.0 mol
[3]
(3) 3.0 mol
(4) 4.0 mol
[OVER]
24 Which half-reaction correctly
reduction?
(1) Mn4+ → Mn3+ + e–
(2) Mn4+ → Mn7+ + 3e–
(3) Mn4+ + e– → Mn3+
(4) Mn4+ + 3e– → Mn7+
28 A nuclear reaction in which two light nuclei
combine to form a more massive nucleus is
called
(1) addition
(3) fusion
(2) fission
(4) substitution
represents
29 The nucleus of a radium-226 atom is unstable,
which causes the nucleus to spontaneously
(1) absorb electrons
(3) decay
(2) absorb protons
(4) oxidize
25 Which indicator is blue in a solution that has a
pH of 5.6?
(1) bromcresol green
(3) methyl orange
(2) bromthymol blue
(4) thymol blue
30 A serious risk factor associated with the operation
of a nuclear power plant is the production of
(1) acid rain
(2) helium gas
(3) greenhouse gases, such as CO2
(4) radioisotopes with long half-lives
26 The Arrhenius theory explains the behavior of
(1) acids and bases
(2) alcohols and amines
(3) isomers and isotopes
(4) metals and nonmetals
27 In which laboratory process could a student use
0.10 M NaOH(aq) to determine the concentration of an aqueous solution of HBr?
(1) chromatography
(2) decomposition of the solute
(3) evaporation of the solvent
(4) titration
P.S./Chem.–Aug. ’08
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
38 Which balanced equation represents a chemical
change?
(1) H2O(ᐉ) + energy → H2O(g)
(2) 2H2O(ᐉ) + energy → 2H2(g) + O2(g)
(3) H2O(ᐉ) → H2O(s) + energy
(4) H2O(g) → H2O(ᐉ) + energy
31 What is the total number of protons in an atom
with the electron configuration 2-8-18-32-18-1?
(1) 69
(3) 118
(2) 79
(4) 197
32 Which two elements have the most similar
chemical properties?
(1) Be and Mg
(3) Cl and Ar
(2) Ca and Br
(4) Na and P
39 When 5 grams of KCl are dissolved in 50. grams
of water at 25°C, the resulting mixture can be
described as
(1) heterogeneous and unsaturated
(2) heterogeneous and supersaturated
(3) homogeneous and unsaturated
(4) homogeneous and supersaturated
33 In the ground state, each atom of an element
has two valence electrons. This element has a
lower first ionization energy than calcium.
Where is this element located on the Periodic
Table?
(1) Group 1, Period 4 (3) Group 2, Period 3
(2) Group 2, Period 5 (4) Group 3, Period 4
40 Which aqueous solution of KI freezes at the
lowest temperature?
(1) 1 mol of KI in 500. g of water
(2) 2 mol of KI in 500. g of water
(3) 1 mol of KI in 1000. g of water
(4) 2 mol of KI in 1000. g of water
34 Which equation shows conservation of mass and
charge?
(1) NH4Br → NH3 + Br2
(2) 2Mg + Fe3+ → Mg2+ + 3Fe
(3) H2SO4 + LiOH → Li2SO4 + H2O
(4) Cu + 2Ag+ → Cu2+ + 2Ag
41 Which compound is a member of the same
homologous series as C3H8?
(3) C5H8
(1) CH4
(2) C4H8
(4) C5H10
35 What is the percent composition by mass of
hydrogen in NH4HCO3 (gram-formula mass =
79 grams/mole)?
(1) 5.1%
(3) 10.%
(2) 6.3%
(4) 50.%
42 Which equation represents an oxidationreduction reaction?
(1) CH4 + 2O2 → CO2 + 2H2O
(2) H2SO4 + Ca(OH)2 → CaSO4 + 2H2O
(3) MgCrO4 + BaCl2 → MgCl2 + BaCrO4
(4) Zn(NO3)2 + Na2CO3 → 2NaNO3 + ZnCO3
36 What is the total number of valence electrons in
a sulfide ion in the ground state?
(1) 8
(3) 16
(2) 2
(4) 18
37 A temperature of 37°C is equivalent to a
temperature of
(1) 98.6 K
(3) 310. K
(2) 236 K
(4) 371 K
P.S./Chem.–Aug. ’08
[5]
[OVER]
46 Given the balanced equation representing a
reaction:
43 Given the balanced equation representing a
reaction:
2KClO3(s) → 2KCl(s) + 3O2(g)
NH3(g) + H2O(ᐉ) → NH4+(aq) + OH–(aq)
The oxidation state of chlorine in this reaction
changes from
According to one acid-base theory, the NH3(g)
molecules act as
(1) –1 to +1
(2) –1 to +5
(1)
(2)
(3)
(4)
(3) +1 to –1
(4) +5 to –1
44 The potential energy diagram for a chemical
reaction is shown below.
Potential Energy (kJ)
47 What volume of 0.120 M HNO3(aq) is needed
to completely neutralize 150.0 milliliters of
0.100 M NaOH(aq)?
(1) 62.5 mL
(3) 180. mL
(2) 125 mL
(4) 360. mL
48 Given the balanced equation representing a
nuclear reaction:
235U
92
(1)
Each interval on the axis labeled “Potential
Energy (kJ)” represents 40 kilojoules. What is
the heat of reaction?
(1) −120 kJ
(2) −40 kJ
(2)
0
−1e
1H
1
(3) 42He
(4) 10n
49 An original sample of the radioisotope
fluorine-21 had a mass of 80.0 milligrams. Only
20.0 milligrams of this original sample remain
unchanged after 8.32 seconds. What is the
half-life of fluorine-21?
(1) 1.04 s
(3) 4.16 s
(2) 2.08 s
(4) 8.32 s
(3) +40 kJ
(4) +160 kJ
45 Given the balanced equation representing a
reaction occurring in an electrolytic cell:
2NaCl(ᐉ) → 2Na(ᐉ) + Cl2(g)
50 Which nuclide is paired with a specific use of
that nuclide?
(1) carbon-14, treatment of cancer
(2) cobalt-60, dating of rock formations
(3) iodine-131, treatment of thyroid disorders
(4) uranium-238, dating of once-living organisms
Where is Na(ᐉ) produced in the cell?
at the anode, where oxidation occurs
at the anode, where reduction occurs
at the cathode, where oxidation occurs
at the cathode, where reduction occurs
P.S./Chem.–Aug. ’08
91
+ 10n → 142
56Ba + 36Kr + 3X + energy
Which particle is represented by X?
Reaction Coordinate
(1)
(2)
(3)
(4)
an acid because they accept H+ ions
an acid because they donate H+ ions
a base because they accept H+ ions
a base because they donate H+ ions
[6]
Part B–2
Answer all questions in this part.
Directions (51–65): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
51 Identify one ion from Table F that can combine with Pb2+(aq) to produce an insoluble
compound. [1]
52 Describe one appropriate laboratory test that can be used to determine the malleability
of a solid sample of an element at room temperature. [1]
53 State two methods to increase the rate of a chemical reaction and explain, in terms of
particle behavior, how each method increases the reaction rate. [2]
Base your answers to questions 54 through 57 on the information below.
Naturally Occurring Isotopes of Copper
Isotope
Notation
Percent Natural
Abundance (%)
Atomic Mass
(atomic mass units, u)
Cu-63
69.17
62.930
Cu-65
30.83
64.928
54 State, in terms of subatomic particles, how an atom of Cu-63 differs from an atom of
Cu-65. [1]
55 What is the total number of electrons in an atom of Cu-65? [1]
56 The atomic mass of Cu-63 is expressed to what number of significant figures? [1]
57 In the space in your answer booklet, show a correct numerical setup for calculating the
atomic mass of copper. [1]
P.S./Chem.–Aug. ’08
[7]
[OVER]
Base your answers to questions 58 and 59 on the information below.
The boiling point of a liquid is the temperature at which the vapor pressure of the
liquid is equal to the pressure on the surface of the liquid. The heat of vaporization of
ethanol is 838 joules per gram. A sample of ethanol has a mass of 65.0 grams and is
boiling at 1.00 atmosphere.
58 Based on Table H, what is the temperature of this sample of ethanol? [1]
59 Calculate the minimum amount of heat required to completely vaporize this sample of
ethanol. Your response must include both a correct numerical setup and the calculated
result. [2]
Base your answers to questions 60 through 62 on the information below.
The equation below represents the reaction between butanoic acid and an unidentified
reactant, X.
H
H
H
H
O
C
C
C
C
H
H
H
OH
+ X
H
H
H
H
O
C
C
C
C
H
H
H
O
H
H
C
C
H
H
H
+
H
O
60 Identify the type of organic reaction represented by the equation. [1]
61 Write the molecular formula of the organic product in the equation.
[1]
62 In the space in your answer booklet, draw a structural formula for the unidentified
reactant, X, in the equation. [1]
P.S./Chem.–Aug. ’08
[8]
H
Base your answers to questions 63 through 65 on the information below.
A piece of magnesium ribbon is reacted with excess hydrochloric acid to produce
aqueous magnesium chloride and hydrogen gas. The volume of the dry hydrogen gas
produced is 45.6 milliliters. The temperature of the gas is 293 K, and the pressure is
99.5 kilopascals.
63 Balance the equation in your answer booklet, using the smallest whole-number
coefficients. [1]
64 Identify the type of bond between the atoms in a molecule of the gas produced in this
laboratory investigation. [1]
65 Calculate the volume this dry hydrogen gas would occupy at STP. Your response must
include both a correct numerical setup and the calculated result. [2]
P.S./Chem.–Aug. ’08
[9]
[OVER]
Part C
Answer all questions in this part.
Directions (66–80): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 66 through 69 on the information below.
In a laboratory, a glass tube is filled with hydrogen gas at a very low pressure. When a
scientist applies a high voltage between metal electrodes in the tube, light is emitted. The
scientist analyzes the light with a spectroscope and observes four distinct spectral lines. The
table below gives the color, frequency, and energy for each of the four spectral lines. The
unit for frequency is hertz, Hz.
Visible Spectrum of Hydrogen
Frequency
(× 1014 Hz)
Energy
(× 10–19 J)
red
4.6
3.0
blue green
6.2
4.1
blue
6.9
4.6
violet
7.3
4.8
Color
66 On the grid in your answer booklet, plot the data from the data table for frequency and
energy. Circle and connect the points, including the point (0,0) that has already been
plotted and circled for you. [1]
67 A spectral line in the infrared region of the spectrum of hydrogen has a frequency of
2.3 × 1014 hertz. Using your graph, estimate the energy associated with this spectral
line. [1]
68 Explain, in terms of subatomic particles and energy states, why light is emitted by the
hydrogen gas. [1]
69 Identify one condition not mentioned in the passage, under which hydrogen gas
behaves most like an ideal gas. [1]
P.S./Chem.–Aug. ’08
[10]
Base your answers to questions 70 through 72 on the information below.
Carbon and oxygen are examples of elements that exist in more than one form in the
same phase.
Graphite and diamond are two crystalline arrangements for carbon. The crystal
structure of graphite is organized in layers. The bonds between carbon atoms within each
layer of graphite are strong. The bonds between carbon atoms that connect different
layers of graphite are weak because the shared electrons in these bonds are loosely held by
the carbon atoms. The crystal structure of diamond is a strong network of atoms in which
all the shared electrons are strongly held by the carbon atoms. Graphite is an electrical
conductor, but diamond is not. At 25°C, graphite has a density of 2.2 g/cm3 and diamond
has a density of 3.51 g/cm3.
The element oxygen can exist as diatomic molecules, O2, and as ozone, O3. At standard
pressure the boiling point of ozone is 161 K.
70 Explain, in terms of electrons, why graphite is an electrical conductor and diamond is
not. Your response must include information about both graphite and diamond. [1]
71 Calculate the volume, in cm3, of a diamond at 25°C that has a mass of 0.200 gram. Your
response must include both a correct numerical setup and the calculated result. [2]
72 Explain, in terms of intermolecular forces, the difference in the boiling points of
O2 and O3 at standard pressure. Your response must include information about both
O2 and O3. [1]
P.S./Chem.–Aug. ’08
[11]
[OVER]
Base your answers to questions 73 through 76 on the information below.
A portable propane-fueled lantern contains a mesh silk bag coated with metal hydroxides.
The primary metal hydroxide is yttrium hydroxide. When the silk bag is installed, it is ignited
and burned away, leaving the metal hydroxide coating. The coating forms metal oxides that
glow brightly when heated to a high temperature.
During a test, a propane lantern is operated for three hours and consumes 5.0 moles of
propane from the lantern’s tank. The balanced equation below represents the combustion
of propane.
C3H8 + 5O2 → 3CO2 + 4H2O + energy
73 At standard pressure, the boiling point of propane is 231 K. In the box in your answer
booklet, draw a particle diagram to represent the phase of the propane as it leaves the
tank at 294 K. Your response must include at least six molecules. [1]
74 Calculate the total mass of propane consumed during the lantern test. Your response
must include both a correct numerical setup and the calculated result. [2]
75 Determine the total number of moles of CO2 produced during the lantern test. [1]
76 Write the formula for the primary metal hydroxide used in the lantern. [1]
Base your answers to questions 77 through 80 on the information below.
When a person perspires (sweats), the body loses many sodium ions and potassium ions.
The evaporation of sweat cools the skin.
After a strenuous workout, people often quench their thirst with sports drinks that
contain NaCl and KCl. A single 250.-gram serving of one sports drink contains 0.055 gram
of sodium ions.
77 In the space in your answer booklet, show a correct numerical setup for calculating the
concentration of sodium ions in this sports drink, expressed as percent by mass. [1]
78 Describe the transfer of energy between the skin and the surroundings as a person
perspires and the sweat evaporates. [1]
79 State why the salts in sports drinks are classified as electrolytes. [1]
80 In the space in your answer booklet, draw a Lewis electron-dot diagram for one of the
positive ions lost by the body as a person perspires. [1]
P.S./Chem.–Aug. ’08
[12]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Wednesday, August 13, 2008 — 12:30 to 3:30 p.m., only
ANSWER SHEET
I Male I Female Grade . . . . . . . . . . . .
Student . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sex:
Teacher . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature
PS/CHEMISTRY
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
CHEMISTRY
Thursday, January 29, 2009 — 1:15 to 4:15 p.m., only
This is a test of your knowledge of chemistry. Use that knowledge to answer all
questions in this examination. Some questions may require the use of the Reference
Tables for Physical Setting/Chemistry. You are to answer all questions in all parts of
this examination according to the directions provided in the examination booklet.
Your answer sheet for Part A and Part B–1 is the last page of this examination
booklet. Turn to the last page and fold it along the perforations. Then, slowly and
carefully, tear off your answer sheet and fill in the heading.
The answers to the questions in Part B–2 and Part C are to be written in your
separate answer booklet. Be sure to fill in the heading on the front of your answer
booklet.
Record the number of your choice for each Part A and Part B–1 multiple-choice
question on your separate answer sheet. Write your answers to the Part B–2 and
Part C questions in your answer booklet. All work should be written in pen, except for
graphs and drawings, which should be done in pencil. You may use scrap paper to
work out the answers to the questions, but be sure to record all your answers on your
separate answer sheet and in your answer booklet.
When you have completed the examination, you must sign the statement printed
at the end of your separate answer sheet, indicating that you had no unlawful
knowledge of the questions or answers prior to the examination and that you have
neither given nor received assistance in answering any of the questions during the
examination. Your answer sheet and answer booklet cannot be accepted if you fail to
sign this declaration.
Notice. . .
A four-function or scientific calculator and a copy of the Reference Tables for Physical
Setting/Chemistry must be available for you to use while taking this examination.
The use of any communications device is strictly prohibited when taking this
examination. If you use any communications device, no matter how briefly, your
examination will be invalidated and no score will be calculated for you.
DO NOT OPEN THIS EXAMINATION BOOKLET UNTIL THE SIGNAL IS GIVEN.
PS/CHEMISTRY
Part A
Answer all questions in this part.
Directions (1–30): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
6 What can be determined if only the atomic
number of an atom is known?
(1) the total number of neutrons in the atom,
only
(2) the total number of protons in the atom,
only
(3) the total number of protons and the total
number of neutrons in the atom
(4) the total number of protons and the total
number of electrons in the atom
1 On the modern Periodic Table, the elements are
arranged in order of increasing
(1) atomic mass
(3) mass number
(2) atomic number
(4) oxidation number
2 Which particle has a mass that is approximately
the same as the mass of a proton?
(1) an alpha particle
(3) a neutron
(2) a beta particle
(4) a positron
3 An atom of an element forms a 2+ ion. In which
group on the Periodic Table could this element
be located?
(1) 1
(3) 13
(2) 2
(4) 17
7 The most common isotope of chromium has a
mass number of 52. Which notation represents
a different isotope of chromium?
4 Which statement describes the relative energy
of the electrons in the shells of a calcium atom?
(1) An electron in the first shell has more energy
than an electron in the second shell.
(2) An electron in the first shell has the same
amount of energy as an electron in the
second shell.
(3) An electron in the third shell has more energy
than an electron in the second shell.
(4) An electron in the third shell has less energy
than an electron in the second shell.
52Cr
24
(3)
24Cr
52
(2)
54Cr
24
(4)
24Cr
54
8 Which Group 14 element is a metalloid?
(1) tin
(3) lead
(2) silicon
(4) carbon
9 Samples of four Group 15 elements, antimony,
arsenic, bismuth, and phosphorus, are in the
gaseous phase. An atom in the ground state of
which element requires the least amount of
energy to remove its most loosely held electron?
(1) As
(3) P
(2) Bi
(4) Sb
5 According to the electron-cloud model of the
atom, an orbital is a
(1) circular path traveled by an electron around
the nucleus
(2) spiral path traveled by an electron toward
the nucleus
(3) region of the most probable proton location
(4) region of the most probable electron
location
P.S./Chem.–Jan. ’09
(1)
10 Which substance can be broken down by chemical
means?
(1) CO
(3) Ca
(2) Ce
(4) Cu
11 During all chemical reactions, mass, energy, and
charge are
(1) absorbed
(3) formed
(2) conserved
(4) released
[2]
19 The net energy released or absorbed during a
reversible chemical reaction is equal to
(1) the activation energy of the endothermic
reaction
(2) the activation energy of the exothermic
reaction
(3) the difference between the potential energy
of the products and the potential energy of
the reactants
(4) the sum of the potential energy of the
products and the potential energy of the
reactants
12 Which formula represents a molecular compound?
(1) Kr
(3) N2O4
(2) LiOH
(4) NaI
13 The bonds in BaO are best described as
(1) covalent, because valence electrons are shared
(2) covalent, because valence electrons are transferred
(3) ionic, because valence electrons are shared
(4) ionic, because valence electrons are transferred
20 A catalyst lowers the activation energy of a
reaction by
(1) providing an alternate reaction pathway
(2) decreasing the heat of reaction
(3) increasing the mass of the reactants
(4) changing the mole ratio of the reactants
14 In which sample of water do the molecules have
the highest average kinetic energy?
(1) 20. mL at 100.°C
(3) 60. mL at 60.°C
(2) 40. mL at 80.°C
(4) 80. mL at 40.°C
15 Which compound is insoluble in water?
(1) calcium bromide
(3) silver bromide
(2) potassium bromide (4) sodium bromide
21 Which element is present in every organic
compound?
(1) carbon
(3) nitrogen
(2) fluorine
(4) oxygen
16 Which element is a brittle solid with low
conductivity at STP?
(1) sulfur
(3) argon
(2) sodium
(4) aluminum
22 Given the balanced equation representing a
reaction:
2Fe + 3Cu2+ → 2Fe3+ + 3Cu
17 Which two samples of gas at STP contain the
same total number of molecules?
(1) 1 L of CO(g) and 0.5 L of N2(g)
(2) 2 L of CO(g) and 0.5 L of NH3(g)
(3) 1 L of H2(g) and 2 L of Cl2(g)
(4) 2 L of H2(g) and 2 L of Cl2(g)
When the iron atoms lose six moles of electrons,
how many moles of electrons are gained by the
copper ions?
(1) 12 moles
(2) 2 moles
18 A reaction is most likely to occur when reactant
particles collide with
(1) proper energy, only
(2) proper orientation, only
(3) both proper energy and proper orientation
(4) neither proper energy nor proper orientation
P.S./Chem.–Jan. ’09
(3) 3 moles
(4) 6 moles
23 Which statement describes electrolysis?
(1) Chemical energy is used to produce an
electrical change.
(2) Chemical energy is used to produce a
thermal change.
(3) Electrical energy is used to produce a
chemical change.
(4) Thermal energy is used to produce a
chemical change.
[3]
[OVER]
24 During which process does an atom gain one or
more electrons?
(1) transmutation
(3) oxidation
(2) reduction
(4) neutralization
28 The only positive ion found in H2SO4(aq) is the
(1) ammonium ion
(3) hydroxide ion
(2) hydronium ion
(4) sulfate ion
29 Which risk is associated with using nuclear
fission to produce energy in a power plant?
(1) depletion of hydrocarbons
(2) depletion of atmospheric oxygen
(3) exposure of workers to radiation
(4) exposure of workers to sulfur dioxide
25 Which substance is an Arrhenius base?
(3) LiOH
(1) CH3OH
(2) CH3Cl
(4) LiCl
26 Which statement describes an alternate theory
of acids and bases?
(1) Acids and bases are both H+ acceptors.
(2) Acids and bases are both H+ donors.
(3) Acids are H+ acceptors, and bases are H+
donors.
(4) Acids are H+ donors, and bases are H+
acceptors.
30 An unstable nucleus loses the most mass if the
nucleus emits
(1) an alpha particle
(3) a positron
(2) a beta particle
(4) a gamma ray
27 Which two compounds are electrolytes?
(1) C6H12O6 and CH3CH2OH
(2) C6H12O6 and HCl
(3) NaOH and HCl
(4) NaOH and CH3CH2OH
P.S./Chem.–Jan. ’09
[4]
Part B–1
Answer all questions in this part.
Directions (31–50): For each statement or question, write on the separate answer sheet the number of the
word or expression that, of those given, best completes the statement or answers the question. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
31 The diagram below represents the bright-line spectra of four elements and a bright-line spectrum
produced by a mixture of two of these elements.
Bright-Line Spectra
400
500
600
700
750
700
750
Barium
Helium
Hydrogen
Lithium
Mixture
400
500
600
Wavelength (nm)
Which two elements are in this mixture?
(1) barium and hydrogen
(2) barium and lithium
33 What is the total number of valence electrons in
an atom of germanium in the ground state?
(1) 8
(3) 14
(2) 2
(4) 4
32 The table below gives information about the
nucleus of each of four atoms.
Nuclei of Four Atoms
Atom
Number of
Protons
Number of
Neutrons
A
6
6
D
6
7
E
7
7
G
7
8
(3) helium and hydrogen
(4) helium and lithium
34 In the formula X2O5, the symbol X could represent an element in Group
(1) 1
(3) 15
(2) 2
(4) 18
How many different elements are represented
by the nuclei in the table?
(1) 1
(2) 2
P.S./Chem.–Jan. ’09
(3) 3
(4) 4
[5]
[OVER]
35 A 50.0-gram block of copper at 10.0°C is
carefully lowered into 100.0 grams of water
at 90.0°C in an insulated container. Which
statement describes the transfer of heat in this
system?
(1) The water loses heat to the block until both
are at 10.0°C.
(2) The block gains heat from the water until
both are at 90.0°C.
(3) The water loses heat and the block gains
heat until both are at the same temperature
that is between 10.0°C and 90.0°C.
(4) The water gains heat and the block loses
heat until both are at the same temperature
that is between 10.0°C and 90.0°C.
41 Which particle diagram represents a mixture of
an element and a compound?
Key
= an atom of an element
= an atom of a different element
(1)
(3)
(2)
(4)
36 The compounds C2H4 and C4H8 have the same
(1) freezing point at standard pressure
(2) boiling point at standard pressure
(3) molecular formula
(4) empirical formula
37 The chemical bond between which two atoms is
most polar?
(1) C–N
(3) S–Cl
(2) H–H
(4) Si–O
42 Starting as a solid, a sample of a substance is
heated at a constant rate. The graph below
shows the changes in temperature of this
sample.
38 What is the total amount of heat absorbed by
100.0 grams of water when the temperature of
the water is increased from 30.0°C to 45.0°C?
(1) 418 J
(3) 12 500 J
(2) 6270 J
(4) 18 800 J
Temperature Versus Time for a Sample
200
Temperature (°C)
180
39 Which process is exothermic?
(1) boiling of water
(2) melting of copper
(3) condensation of ethanol vapor
(4) sublimation of iodine
160
140
120
100
80
60
40
20
40 Which sample, when dissolved in 1.0 liter of
water, produces a solution with the lowest
freezing point?
(1) 0.1 mol of C2H5OH
(2) 0.1 mol of LiBr
(3) 0.2 mol of C6H12O6
(4) 0.2 mol of CaCl2
P.S./Chem.–Jan. ’09
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16
Time (min)
What is the melting point of the sample and the
total time required to completely melt the
sample after it has reached its melting point?
(1) 50°C and 3 min
(2) 50°C and 5 min
[6]
(3) 110°C and 4 min
(4) 110°C and 14 min
43 Which compound is an alkyne?
(3) C4H8
(1) C2H2
(2) C2H4
(4) C4H10
48 Which nuclide has a half-life that is less than one
minute?
(1) cesium-137
(3) phosphorus-32
(2) francium-220
(4) strontium-90
44 What is the oxidation number of sulfur in
Na2S2O3?
(1) −1
(3) +6
(2) +2
(4) +4
49 The table below indicates the stability of six
nuclides.
Stability of Six Nuclides
Nuclide
45 Which formula represents an unsaturated
hydrocarbon?
H H
H
C
C
H
C
H
H
H
H
H
H C
C
C
H
H
H
(1)
(3)
H
H
H
H C
C
C
H
H
H
(2)
Cl
H
H
H
O
H C
C
C
H
H
Stability
C-12
stable
C-14
unstable
N-14
stable
N-16
unstable
O-16
stable
O-19
unstable
All atoms of the unstable nuclides listed in this
table have
H
(1)
(2)
(3)
(4)
(4)
46 Which balanced equation represents a redox
reaction?
(1) PCl5 → PCl3 + Cl2
(2) KOH + HCl → KCl + H2O
(3) LiBr → Li+ + Br−
(4) Ca2+ + SO42− → CaSO4
an odd number of neutrons
an odd number of protons
more neutrons than protons
more protons than neutrons
50 Cobalt-60 and iodine-131 are radioactive
isotopes that are used in
(1) dating geologic formations
(2) industrial measurements
(3) medical procedures
(4) nuclear power
47 A 25.0-milliliter sample of HNO3(aq) is neutralized by 32.1 milliliters of 0.150 M KOH(aq).
What is the molarity of the HNO3(aq)?
(1) 0.117 M
(3) 0.193 M
(2) 0.150 M
(4) 0.300 M
P.S./Chem.–Jan. ’09
[7]
[OVER]
Part B–2
Answer all questions in this part.
Directions (51–66): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
51 In the box in your answer booklet, draw a Lewis electron-dot diagram for an atom of
boron. [1]
52 Explain, in terms of atomic structure, why the noble gas neon is an unreactive element. [1]
53 Given the equation representing a reaction at equilibrium:
N2(g) + 3H2(g) 2NH3(g)
Explain, in terms of collision theory, why the rate of the forward reaction decreases
when the concentration of N2(g) is decreased. [1]
Base your answers to questions 54 and 55 on the information below.
A 4.86-gram sample of calcium reacted completely with oxygen to form 6.80 grams of
calcium oxide. This reaction is represented by the balanced equation below.
2Ca(s) + O2(g) → 2CaO(s)
54 Determine the total mass of oxygen that reacted. [1]
55 Explain, in terms of electrons, why the radius of a calcium ion is smaller than the radius
of a calcium atom. [1]
P.S./Chem.–Jan. ’09
[8]
Base your answers to questions 56 through 58 on the information below.
The compounds NH4Br(s) and NH3(g) are soluble in water. Solubility data for
NH4Br(s) in water are listed in the table below.
Solubility of NH4Br in H2O
Mass of NH4Br
Temperature
per 100. g of H2O
(°C)
(g)
0
60.
20.
75.
40.
90.
60.
105.
80.
120.
100.
135.
56 On the grid in your answer booklet, plot the data from the data table. Circle and
connect the points. [1]
57 Determine the total mass of NH4Br(s) that must be dissolved in 200. grams of H2O at
60.°C to produce a saturated solution. [1]
58 Compare the solubilities of NH4Br(s) and NH3(g), each in 100. grams of H2O, as
temperature increases at standard pressure. Your response must include both
NH4Br(s) and NH3(g). [1]
Base your answers to questions 59 through 61 on the information below.
Carbon forms molecular compounds with some elements from Group 16. Two of these
compounds are carbon dioxide, CO2, and carbon disulfide, CS2.
Carbon dioxide is a colorless, odorless gas at room temperature. At standard temperature
and pressure, CO2(s) changes directly to CO2(g).
Carbon disulfide is formed by a direct reaction of carbon and sulfur. At room temperature,
CS2 is a colorless liquid with an offensive odor. Carbon disulfide vapors are flammable.
59 Identify one physical property and one chemical property of CS2. [1]
60 State what happens to the potential energy of CO2 molecules during this phase change
of CO2. [1]
61 Compare the intermolecular forces in CO2 and CS2 at room temperature. [1]
P.S./Chem.–Jan. ’09
[9]
[OVER]
Base your answers to questions 62 through 64 on the data table below.
Formulas and Boiling Points
of Selected Alkanes
Name
Formula
Boiling Point at
1 Atm (°C)
methane
CH4
–162
ethane
C2H6
–89
propane
C3H8
–42
butane
C4H10
–0.5
pentane
C5H12
36
62 In the space in your answer booklet, draw a structural formula for butane. [1]
63 At standard pressure and 298 K, which alkane is a liquid? [1]
64 What is the boiling point of propane at 1 atmosphere, in kelvins? [1]
Base your answers to questions 65 and 66 on the information below.
The balanced equation below represents the reaction between magnesium metal and
hydrochloric acid to produce aqueous magnesium chloride and hydrogen gas.
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
A piece of Mg(s) has a volume of 0.0640 cubic centimeters. This piece of Mg(s)
reacts completely with HCl(aq) to produce H2(g). The H2(g) produced has a volume of
112 milliliters and a pressure of 1.00 atmosphere at 298 K.
65 The volume of the piece of Mg(s) is expressed to what number of significant figures? [1]
66 In the space in your answer booklet, show a correct numerical setup for calculating the
volume of the H2(g) produced if the conditions are changed to STP. [1]
P.S./Chem.–Jan. ’09
[10]
Part C
Answer all questions in this part.
Directions (67–81): Record your answers in the spaces provided in your answer booklet. Some questions
may require the use of the Reference Tables for Physical Setting/Chemistry.
Base your answers to questions 67 and 68 on the information below.
Underground iron pipes in contact with moist soil are likely to corrode. This corrosion
can be prevented by applying the principles of electrochemistry. Connecting an iron pipe
to a magnesium block with a wire creates an electrochemical cell. The magnesium block
acts as the anode and the iron pipe acts as the cathode. A diagram of this system is shown
below.
Cross-Sectional View of
Underground Pipe Protection System
Ground
level
Moist sand
and gravel
Wire
Mg block
Fe pipe
Moist soil
67 State the direction of the flow of electrons between the electrodes in this cell. [1]
68 Explain, in terms of reactivity, why magnesium is preferred over zinc to protect underground iron pipes. Your response must include both magnesium and zinc. [1]
P.S./Chem.–Jan. ’09
[11]
[OVER]
Base your answers to questions 69 through 71 on the information below.
In a laboratory, 0.100 mole of colorless hydrogen iodide gas at room temperature is
placed in a 1.00-liter flask. The flask is sealed and warmed, causing the HI(g) to start
decomposing to H2(g) and I2(g). Then the temperature of the contents of the flask is kept
constant.
During this reaction, the contents of the flask change to a pale purple-colored mixture
of HI(g), H2(g), and I2(g). When the color of the mixture in the flask stops changing, the
concentration of I2(g) is determined to be 0.013 mole per liter. The relationship between
concentration and time for the reactant and products is shown in the graph below.
Concentration of Reactant and
Products Versus Time
0.100
0.090
Concentration (M)
0.080
Reactant
0.070
0.060
0.050
0.040
0.030
0.020
Each product
0.010
0.000
Time
69 Write a balanced equation to represent the decomposition reaction occurring in the
flask. [1]
70 State, in terms of concentration, evidence that indicates the system in the flask has
reached equilibrium. [1]
71 Calculate the mass of I2(g) in the flask at equilibrium. Your response must include both
a correct numerical setup and the calculated result. [2]
P.S./Chem.–Jan. ’09
[12]
Base your answers to questions 72 through 74 on the information below.
Soil pH can affect the development of plants. For example, a hydrangea plant produces
blue flowers when grown in acidic soil but pink flowers when grown in basic soil.
Evergreen plants can show a yellowing of foliage, called chlorosis, when grown in soil that
is too basic.
Acidic soil can be neutralized by treating it with calcium hydroxide, Ca(OH)2, commonly
called slaked lime. Slaked lime is slightly soluble in water.
72 Compare the hydrogen ion concentration to the hydroxide ion concentration in soil
when a hydrangea plant produces pink flowers. [1]
73 An evergreen plant has yellowing foliage. The soil surrounding the plant is tested with
methyl orange and bromthymol blue. Both indicators turn yellow in the soil tests.
State, in terms of pH value, why the yellowing of the plant is not due to chlorosis. [1]
74 Write an equation, using symbols or words, for the neutralization of the ions in acidic
soil by the ions released by slaked lime in water. [1]
Base your answers to questions 75 through 77 on the information below.
A fluorescent light tube contains a noble gas and a drop of mercury. When the
fluorescent light operates, the Hg is a vapor and there are free-flowing Hg ions and
electrons in the tube. The electrons collide with Hg atoms that then emit ultraviolet (UV)
radiation.
The inside of the tube is coated with a mixture of several compounds that absorbs
UV radiation. Ions in the coating emit a blend of red, green, and blue light that together
appears as white light. The compound that produces red light is Y2O3. The compound that
produces green light is CeMgAl11O19. The compound that produces blue light is
BaMgAl10O17.
75 Write the chemical name of the compound that produces red light. [1]
76 Calculate the percent composition by mass of aluminum in the compound that
produces green light. Your response must include both a correct numerical setup and
the calculated result. [2]
77 Explain, in terms of both electrons and energy, how ions in the coating emit light. [1]
P.S./Chem.–Jan. ’09
[13]
[OVER]
Base your answers to questions 78 and 79 on the information below.
A substance known as heavy water can be obtained from ordinary water and could be a
significant source of energy in the future. Heavy water contains deuterium, H-2. Instead
of the two hydrogen atoms in a typical water molecule, a heavy water molecule has two
deuterium atoms. In 3.78 kilograms of ordinary water, the percent composition by mass of
heavy water is approximately 0.0156%.
Deuterium atoms completely ionize at approximately 108 K. The result is an ionized gas
consisting of electrons and deuterons (the nuclei of deuterium). A triton is the nucleus of a
tritium atom, H-3. These particles react according to the equations below. In the second
equation, X represents an unidentified product.
2H
1
+ 21H → 31H + 11H + energy
2H
1
+ 31H → 42He + X + energy
78 Calculate the mass of heavy water in a 3.78-kilogram sample of ordinary water. Your
response must include both a correct numerical setup and the calculated result. [2]
79 Identify particle X in the second nuclear equation. Your response must include the
symbol, atomic number, and mass number of the particle. [1]
Base your answers to questions 80 and 81 on the information below.
Ethyl butanoate is an organic compound that contributes to the odor of pineapple.
Ethyl butanoate is one of the products formed by the reaction of butanoic acid with ethanol.
80 Identify two differences in the structures between a molecule of butanoic acid and a
molecule of ethanol. Each of your responses must include both compounds. [2]
81 Identify the type of organic reaction that produces the compound that contributes to
the odor of pineapple. [1]
P.S./Chem.–Jan. ’09
[14]
The University of the State of New York
REGENTS HIGH SCHOOL EXAMINATION
PHYSICAL SETTING
Tear Here
CHEMISTRY
Thursday, January 29, 2009 — 1:15 to 4:15 p.m., only
ANSWER SHEET
I Male I Female Grade . . . . . . . . . . . .
Student . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sex:
Teacher . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
School . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Record your answers to Part A and Part B–1 on this answer sheet.
Part B–1
Part A
1 ............
11 . . . . . . . . . . . .
21 . . . . . . . . . . .
31 . . . . . . . . . . . .
41 . . . . . . . . . . . .
2 ............
12 . . . . . . . . . . . .
22 . . . . . . . . . . .
32 . . . . . . . . . . . .
42 . . . . . . . . . . . .
3 ............
13 . . . . . . . . . . . .
23 . . . . . . . . . . .
33 . . . . . . . . . . . .
43 . . . . . . . . . . . .
4 ............
14 . . . . . . . . . . . .
24 . . . . . . . . . . .
34 . . . . . . . . . . . .
44 . . . . . . . . . . . .
5 ............
15 . . . . . . . . . . . .
25 . . . . . . . . . . .
35 . . . . . . . . . . . .
45 . . . . . . . . . . . .
6 ............
16 . . . . . . . . . . . .
26 . . . . . . . . . . .
36 . . . . . . . . . . . .
46 . . . . . . . . . . . .
7 ............
17 . . . . . . . . . . . .
27 . . . . . . . . . . .
37 . . . . . . . . . . . .
47 . . . . . . . . . . . .
8 ............
18 . . . . . . . . . . . .
28 . . . . . . . . . . .
38 . . . . . . . . . . . .
48 . . . . . . . . . . . .
9 ............
19 . . . . . . . . . . . .
29 . . . . . . . . . . .
39 . . . . . . . . . . . .
49 . . . . . . . . . . . .
10 . . . . . . . . . . . .
20 . . . . . . . . . . . .
30 . . . . . . . . . . .
40 . . . . . . . . . . . .
50 . . . . . . . . . . . .
Part B–1 Score
Part A Score
Write your answers to Part B–2 and Part C in your answer booklet.
Tear Here
The declaration below should be signed when you have completed the examination.
I do hereby affirm, at the close of this examination, that I had no unlawful knowledge of the questions or answers prior to
the examination and that I have neither given nor received assistance in answering any of the questions during the examination.
Signature