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Chemistry 2202
Bishops College
Final Exam - June 2004
1
Name: _______________________
Teacher: ______________________
Part A: Multiple Choice (Value: 50 points)
1.
The number “84" in the name krypton-84 represents:
a.
the atomic number
b.
the mass number
c.
the number of neutrons
d.
the sum of the protons and electrons
2.
The basic SI unit which measures the amount of substance is:
a.
Avogadro's number
c.
the mole
b.
the molecule
d.
the representative particle
3.
How many moles of SO3 are in 2.4  1024 molecules of SO3?
c.
4.0 mol
a.
2.9  10-23 mol
b.
0.25 mol
d.
3.4  1022 mol
4.
How many grams of N2O4 are in 1.25 mol of N2O4?
a.
0.0136 g
c.
b.
0.0800 g
d.
73.6 g
115 g
How many iodine atoms are in 4.67g of I2 (s)?
a.
0.0369 atoms
b.
1.11  1022 atoms
2.22  1022 atoms
5.54  1021 atoms
5.
6.
7.
8.
9.
c.
d.
What volume does 2.25 mol of nitrogen occupy at STP?
a.
0.100 L
c.
b.
9.96 L
d.
50.4 L
63.0 L
What is the mass of 8.00L of helium gas at STP?
a.
0.0893 g
b.
1.43 g
11.2 g
717 g
c.
d.
All of the following are empirical formulas EXCEPT:
a.
CaCl2
c.
b.
N2O4
d.
Na2SO4
Pb2(SO4)4
The empirical formula of a compound is CH2F. The true molar mass of this compound is
99.1 g/mol. The molecular formula of the compound is:
a.
CH2F
c.
C3H6F3
b.
C2H4F2
d.
C4H8F4
Chemistry 2202
Bishops College
Final Exam - June 2004
2
10.
Which is true of any chemical reaction?
a.
The mass of the products is always greater than the mass of the reactants.
b.
The mass of the reactants equals the mass of the products.
c.
The mass of the reactants increases.
d.
The mass of the products is always less than the mass of the reactants.
11.
When the equation below is completed and balanced, the quantity of hydrochloric acid
required to react with 0.240 mol of calcium hydroxide in the above equation is
____ HCl(aq) + ____ Ca(OH)2(s)  ___________ + _____________
a.
b.
12.
0.120 mol
0.240 mol
c.
d.
0.360 mol
0.480 mol
How many moles of KClO3 are needed to form 2.80 L of O2, measured at STP, according
to the following equation?
2 KClO3(s)  2 KCl(s) + 3 O2(g)
a.
b.
13.
0.0833 mol
0.125 mol
c.
d.
0.188 mol
41.8 mol
What volume of 0.100 M Pb(NO3)2(aq) is required to react completely with 45.6 mL of
0.225 M HCl(aq) according to the reaction below?
Pb(NO3)2(aq) + 2 HCl(aq)  PbCl2(s) + 2 HNO3(aq)
a.
b.
0.0420L
0.0513L
c.
d.
0.103L
0.205 L
14.
A student carries out a reaction in which the theoretical yield of product is 22.4 g. She
determines that she has a percent yield of 85.2 %. How many grams of product did she
actually recover?
a.
19.1 g
c.
26.3 g
b.
22.4 g
d.
85.2 g
15.
The reaction of methane and water is one way to prepare hydrogen.
CH4(g) + 2 H2O(g) CO2(g) + 4 H2(g)
If 0.320 mol of methane reacts with 0.530 mol of water, what is the limiting reagent?
a.
CH4(g)
c.
H2(g)
b.
CO2(g)
d.
H2O(g)
16.
A phosphorus atom has _____ lone pair(s) of valence electrons.
a.
none
c.
two
b.
one
d.
three
17.
A covalent bond forms:
a.
between metals and nonmetals
b.
when an element becomes a noble gas
c.
when atoms share electrons
d.
when electrons are transferred from one atom to another
Chemistry 2202
18.
Bishops College
Final Exam - June 2004
Which molecule below will have a triple covalent bond?
a.
F2
c.
b.
H2
d.
3
N2
O2
19.
We would expect a bond formed between a silicon atom and an oxygen atom to be:
a.
a metallic bond
c.
a polar covalent bond
b.
a nonpolar covalent bond
d.
an ionic bond
20.
Forces of attraction which arise between instantaneous dipoles set up in adjacent atoms or
molecules are called:
a.
covalent bonds
c.
hydrogen bonds
b.
dipole - dipole forces
d.
London dispersion forces
21.
Which is the correct Lewis dot diagram for SF2?
a.
b.
22.
23.
F
S F
F S F
c.
d.
F
S F
F
S F
Which of the bonds below is least polar?
a.
C—F
b.
C—H
c.
d.
C—N
C—O
The shape of the H2S molecule is:
a.
bent or v-shaped
b.
linear
c.
d.
pyramidal
trigonal planar
24.
Which substance exhibits London dispersion forces, dipole-dipole forces, and hydrogen
bonding?
a.
H2O2
c.
NH4Cl
b.
NH2F
d.
PCl2H
25.
Which of the following will have the strongest London Dispersion forces?
a.
C4H9OH
c.
OCl2
b.
NI3
d.
SO3
26.
The shape about a central atom with 3 bonding groups of electrons and 0 lone pairs is:
a.
bent
c.
tetrahedral
b.
pyramidal
d.
trigonal planar
27.
Which of the following compounds contains a hydrogen bond?
a.
CH4
c.
CH3F
b.
C2H5OH
d.
CH3Br
Chemistry 2202
Bishops College
Final Exam - June 2004
4
28.
Which compound would most likely have the greatest ionic character?
a.
CaO
c.
KF
b.
CO
d.
LiH
29.
Which of the following molecules is polar?
a.
HCl
b.
H-C≡C-H
c.
d.
N2
CCl4
30.
Which of the following best describes the variation of the electronegativity of the
elements with respect to their position on the periodic table?
a.
Increases across a period; increases down a group.
b.
Increases across a period; decreases down a group.
c.
Decreases across a period; increases down a group.
d.
Decreases across a period; decreases down a group.
31.
Which of the following causes the boiling point of HF to be much higher than that of HCl
or HBr?
a.
covalent bonds
c.
hydrogen bonds
b.
dipole-dipole attractions
d.
London Dispersion forces
32.
A crystalline solid with a high melting point which conducts electricity only when molten or
dissolved in water is:
a.
a molecular compound
c.
a metal
b.
an ionic compound
d.
a network covalent solid
33.
What characteristic of metals makes them good electrical conductors?
a.
They have mobile valence electrons.
b.
They have mobile protons.
c.
They have mobile cations.
d.
Their crystal structures can be rearranged easily.
34.
Which substance is most likely to exist as a macromolecule?
a.
H2O
c.
NaCl
b.
Mg
d.
SiO2
35.
Which of the following is an example of a homogeneous mixture?
a.
chocolate chips in chocolate chip cookies
b.
raisins in Raisin Bran cereal
c.
sand sitting at the bottom of a glass of water
d.
vinegar that has been diluted with water
36.
Carbon disulfide, CS2, is a nonpolar solvent. Which of these would you expect to be
soluble in CS2 ?
a.
CaCO3
c.
H2O
b.
CCl4
d.
SnS2
37.
Rubbing alcohol is a 70% (v/v) 2-propanol/water mixture. What volume of rubbing
alcohol will contain 15 mL of 2-propanol?
a.
0.0467 ml
c.
21.4 mL
b.
10.5 mL
d.
24.6 mL
Chemistry 2202
38.
Bishops College
Final Exam - June 2004
Which substance will partially ionize in water?
a.
CH3COOH
b.
HBr
5
c.
d.
CH3OH
Na2SO4
39.
What is the mole fraction of water in a solution that contains 7 mol of ethanol and 3 mol
of water?
a.
0.3
c.
0.7
b.
0.6
d.
0.8
40.
What are the ion concentrations in a 0.12 M solution of BaCl2? (Note: [ ] is the symbol
for concentration)
a.
[Ba2+] = 0.12 M and [Cl-] = 0.12 M
b.
[Ba2+] = 0.12 M and [Cl-] = 0.060 M
c.
[Ba2+] = 0.12 M and [Cl-] = 0.24 M
d.
[Ba2+] = 0.060 M and [Cl-] = 0.060 M
41.
What is the molarity of a solution that contains 4 moles of solute in 2 litres of solution?
a.
2 mol/L
c.
5 mol/L
b.
4 mol/L
d.
8 mol/L
42.
Which statement explains why the element carbon forms so many compounds?
a.
Carbon atoms combine readily with oxygen.
b.
Carbon atoms have very high electronegativity.
c.
Carbon readily forms ionic bonds with other carbon atoms.
d.
Carbon readily forms covalent bonds with other carbon atoms.
43.
What is the name of the molecule on the right?
a.
butane
b.
pentane
c.
propane
d.
hexane
44.
CH2
H3C
CH2
CH2
CH3
CH2
Which is the condensed structural diagram for 4,4-dimethyl-2-hexyne?
H3C
C
C
CH3
CH3
CH2
CH2
C
CH2 CH3
HC
C
CH2 C
CH2
H3C
b.
CH2
CH3
a.
C
C
CH2 CH3
CH3
c.
CH3
CH3
CH2
CH2
C
CH3
CH3
HC
d.
C
CH2 C
CH3
CH3
Chemistry 2202
45.
Bishops College
Final Exam - June 2004
What is the name for the molecule on the right?
a.
cis-2-ethyl-2-pentene
b.
trans-2-ethyl-2-pentene
c.
cis-3-methyl-3-hexene
d.
trans-3-methyl-3-hexene
H3C
CH3
C
H
What is the IUPAC name of the compound on the right?
a.
butylbenzene
b.
propylcyclohexane
c.
propylbenzene
d.
butylcyclohexane
47.
Which molecule is NOT an isomer of C5H12?
49.
CH2
C
46.
48.
6
a.
c.
b.
d.
CH2 CH3
Which of the following compounds has the lowest boiling point?
a.
c.
b.
d.
Which molecule is methyl propanoate?
H3C
CH2
C
O
CH3
HC
O
a.
c.
CH2
CH2
O
O
O
b.
50.
H3C
H3C
CH2
CH2
CH3
What is the name of the molecule on the right?
a.
1-ethoxypropane
b.
1-ethoxypentane
c.
3-ethoxypropane
d.
3-ethoxypentane
d.
CH3
CH2
C
O
O
CH3
Chemistry 2202
Bishops College
Final Exam - June 2004
7
Part B (Value: 50 points)
Read all instructions carefully. Answer all questions in the space provided.
51.
A hydrocarbon has a percent composition of 85.6% C and 14.4 % H and a molar mass of
56.12 g/mol.
a.
Determine the molecular formula of the hydrocarbon. Show all workings. (3%)
b.
Could the hydrocarbon be an alkane, alkene, alkyne, cycloalkane, and/or a
cylcoalkene? Briefly explain your choice(s), using either general formulas or units
of unsaturation in your answer. (2%)
52.
0.250 g sodium hydroxide are required to neutralize 75.0 ml of sulfuric acid. Write the
balanced equation below, and determine the concentration of the sulfuric acid. (4%)
53.
Mercury (II) oxide decomposes into its elements when heated.
____ HgO(s)  _____ Hg(l) + _____ O2(g)
a.
Calculate the mass of mercury expected when 0.450 mol of mercury (II) oxide is
heated. (2%)
Chemistry 2202
b.
54.
Bishops College
Final Exam - June 2004
8
If 85.3 g of liquid mercury is collected, calculate the percent yield of mercury.
(1%)
Acetylene gas, C2H2, is produced by adding water to calcium carbide, CaC2, as shown by
the balanced equation below:
CaC2(s) +
2 H2O(l) 
C2H2(g) + Ca(OH)2(aq)
What volume of acetylene gas at STP is produced by adding 1.80 g of water to 5.00 g of
calcium carbide? Show all calculations, including your determination of the limiting
reactant. (6%)
55.
For each of the following: (6%)
a.
draw the correct Lewis Dot (Electron Dot) Diagrams
b.
draw the correct VSEPR shape diagram; draw in all bond dipoles
c.
name the shape(s)
d.
state whether the molecule is either polar or nonpolar
Lewis Dot Diagrams
(i) CHF3
(ii) C2F4
(iii) NH3
Shape Diagram With
Bond Dipoles
Shape Name
Polar or
Nonpolar
Chemistry 2202
e.
Bishops College
Final Exam - June 2004
9
Fill in the table below to analyse the above compounds for all intermolecular
forces present. Clearly order the substances from lowest boiling point(1) to
highest boiling point (6%).
# of electrons Intermolecular Forces Present (LDF, D-D,
H-Bond)
Order of Boiling Point
(1-lowest, 3-highest)
(i) CHF3
(ii) C2F4
(iii) NH3
56.
Explain why sodium is easily shaped, but sodium chloride is brittle. Use diagrams to
illustrate the bonding in each. (2%)
57.
What is the molar concentration of a solution made from 12.0 g of sodium bromide
dissolved in 40.0 ml of solution? (2%)
58.
What is the final concentration of a 1.35mol/L solution which is diluted from 125mL to
3.25L? (2%)
Chemistry 2202
59.
60.
Bishops College
Final Exam - June 2004
10
Use the Activity Series to determine if the single replacement reaction will proceed. If it
doesn’t, indicate by writing "No reaction". If it does, write balanced chemical reactions
(including states) for the following: (2%)
a.
A strip of magnesium is put into a solution of nickel (III) nitrate.
b.
Iodine is mixed into a solution of magnesium chloride
Write dissociation / ionization / dispersion equations to show how each compound
dissolves in water. (3%)
a.
Na2SO4 (s)
b.
HCN(aq)
c.
C5H5OH(l)
61.
Calculate the concentration of sulfate ions in a solution made by dissolving 2.69 g of
aluminum sulfate in a 150.0 mL solution. (3%)
62.
Complete the questions on hydrocarbon reactions:
a.
Draw a structural diagram and name the MAJOR product of the following
reaction: (3%)
CH3
CH2
CH2
CH2
CH
+ HOH 
Reaction type: _____________
Product name: _____________________
Chemistry 2202
b.
Bishops College
Final Exam - June 2004
Complete the reaction below by drawing a structural diagram and naming one
organic product of the following reaction: (2%)
H
H
H
H
C
H
C
C
H
C
H
H
H
c.
11
H
+ 1 Cl2

+ HCl
How many other organic products are possible for the reaction in (b), assuming
each butane molecule only substitutes once? (1%)