Download AP Chemistry Review Assignment Brown and LeMay: Chemistry the

AP Chemistry Review Assignment
Brown and LeMay: Chemistry the Central Science
Chapter 1 “Introduction: Matter and Measurement” Assignments
Classification and Properties of Matter
Read: pp. 1-12; Exercises: p.29: #11,15,16
11. Classify each of the following as a pure substance or a mixture; if a mixture, indicate whether it is homogeneous
or heterogeneous:
a) rice pudding
b) seawater
c) magnesium
d) gasoline
15. A solid white substance A is heated strongly in the absence of air. It decomposes to form a new white substance B
and a gas C. The gas has exactly the same properties as the product obtained when carbon is burned in an excess
of oxygen. Based on these observations, can we determine whether solids A and B and the gas C are elements or
compounds? Explain your conclusions for each substance.
16. In the process of attempting to characterize a substance, a chemist makes the following observations:
The substance is a silvery white, lustrous metal. It melts at 649oC and boils at 1105oC. Its density at 20oC is 1.738
g/cm3. The substance burns in air, producing an intense white light. It reacts with chlorine to give a brittle white
solid. The substance be pounded into thin sheets or drawn into wires. It is a good conductor of electricity.
Which of these characteristics are physical properties, and which are chemical properties?
Units of Measurement
Read: pp. 13-19; Exercises: p. 32: #23,24,27
23. What decimal power do the following abbreviations represent?
a) d
b) c
c) f
d) μ
a. M
b. k
c. n
d. m
e. p
24.
Use the appropriate metric prefixes to write the following measurements without use of exponents:
a)
b)
c)
d)
e)
f)
g)
27.
6.35 x 10-2 L
6.5 x 10-4 s
9.5 x 10-4 m
4.23 x 10-9 m3
12.5 x 10-8 kg
3.5 x 10-10 g
6.54 x 109 fs
a)
A sample of carbon tetrachloride, a liquid once used in dry cleaning, has a mass of 39.73 g and
a volume of 25.0 mL at 25oC. What is its density at this temperature? Will carbon tetrachloride
float on water?
b) The density of platinum is 21.45 g/cm3 at 20oC. Calculate the mass of 75.00 cm3 of platinum at this
temperature.
c) The density of magnesium is 1.738 g/cm3 at 20oC. What is the volume of 87.50 g of this metal at this
temperature?
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Uncertainty in Measurement
Read: pp. 20-24; Exercises: pp. 32,33: #33, 35, 39
33. Indicate which of the following are exact numbers:
a) the mass of a paper clip
b) the surface area of a dime
c) the number of inches in a mile
d) the number of ounces in a pound
e) the number of microseconds in a week
f) the number of pages in your textbook
35.
What is the number of significant figures in each of the following measured quantities:
a) 358 kg
b) 0.0054 s
c) 6.3050 cm
d) 0.0105 L
e) 7.0500 x 10-3 m3
39.
Carry out the following operations, and express the answers with the appropriate numbers of significant
figures:
a) 12.0550 + 9.05
b) 257.2 - 19.789
c) (6.21 x 103)(0.1050)
d) 0.0577/75.3
Dimensional Analysis
Read: pp. 24-29; Exercises: p. 33: #43, 48, 52
43. Perform the following conversions:
a) 0.076 L to mL
b) 5.0 x 10-8 m to nm
c) 6.88 x 105 ns to s
d) 0.50 lb to g
e) 5.850 gal/hr to L/s
48. a) If an electric car is capable of going 225 km on a single charge, how many charges will it need to travel from
Boston, Massachusetts, to Miami, Florida, a distance of 1486 mi, assuming that the trip begins with a full charge?
b) If a migrating loon flies at an average speed of 14 m/s, what is its average speed in mi/hr?
c) What is the engine piston displacement in liters of an engine whose displacement is listed as 450 in3?
d) In March 1989, the Exxon Valdez ran aground and spilled 240,000 barrels of crude petroleum off the coast of
Alaska. One barrel of petroleum is equal to 42 gal. How many liters of petroleum were spilled?
53. The Morgan silver dollar has a mass of 26.73 g. By law, it was required to contain 90% silver, with the remainder
being copper.
a) When the coin was minted in the late 1800s, silver was worth $1.18 per troy ounce (31.1 g).
At this price, what is the value of the silver in the silver dollar?
b) Today, silver sells for $13.25 per troy ounce.
How many Morgan silver dollars are required to obtain $25.00 worth of pure silver?
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Chapter 2 “Atoms, Molecules and Ions” Assignments
The Atomic Theory and The Discovery of Atomic Structure
Read: pp. 37-42; Exercises: pp. 69-71: #1, 15, 16,
1.
A negatively charged particle is caused to move between two electrically charged plates, as illustrated
below
a) Why does the path of the charged particle bend?
b) As the charge on the plates is increased, would you expect the bending to increase, decrease, or stay the
same?
c) As the mass of the particle is increased while the speed of the particles remains the same, would you
expect the bending to increase, decrease, or stay the same?
d) An unknown particle is sent through the apparatus. Its path is deflected in the opposite direction from
the negatively-charged particle, and it is deflected by a smaller magnitude. What can you conclude about
this unknown particle?
15.
a)
As shown in Figure 2.5 above, the positively-charged plate is above the negatively-charged plate.
What do you think would be the effect on the rate of oil drops descending if the charges on the plates
were reversed (negative above positive)?
b) In his original series of experiments, Millikan measured the charge on 58 separate oil drops. Why do you
suppose he chose so many drops before reaching his final conclusions?
16. Millikan determined the charge on the electron by studying the static charges on oil drops falling in an electric
field. A student carried out this experiment using several oil drops for her measurements and calculated the
charges on the drops. She obtained the following data:
Droplet
A
B
C
D
Calculated Charge (C)
1.60 x 10-19
3.15 x 10-19
4.81 x 10-19
6.31 x 10-19
a) What is the significance of the fact that the droplets carried different charges?
b) What conclusion can the student draw from these data regarding the charge of the electron?
c) What value (and to how many significant figures) should she report for the electronic charge?
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The Modern View of Atomic Structure and Atomic Weights
Read: pp. 43-48; Exercises: pp. 71,72: # 17, 20, 23, 25, 29, 31
17. The radius of an atom of krypton (Kr) is about 1.9 A.
a) Express this distance in nanometers (nm) and in picometers (pm).
b) How many krypton atoms would have to be lined up to span 1.0 mm?
c) If the atom is assumed to be a sphere, what is the volume in cm3 of a single Kr atom?
20. Determine whether each of the following statements is true or false; if false, correct the statement to make it true:
a) The nucleus has most of the mass and comprises most of the volume of an atom;
b) Every atom of a given element has the same number of protons;
c) The number of electrons in an atom equals the number of neutrons in the atom;
d) The protons in the nucleus of the helium atom are held together by a force called the strong nuclear force.
23. How many protons, neutrons, and electrons are in the following atoms:
a) 40Ar
b) 65Zn
c) 70Ga
d) 80Br
e) 184W
f) 243Am
25. Fill in the gaps in the following table assuming each column represents a neutral atom:
Symbol
Protons
Neutrons
52
Cr
25
30
Electrons
82
64
48
Mass number
86
222
207
29. a) What isotope is used as the standard in establishing the atomic mass scale?
b) The atomic weight of boron is reported as 10.81, yet no atom of boron has the mass of
10.81 amu. Explain.
31. Only two isotopes of copper occur naturally, 63Cu (atomic mass = 62.9296 amu; abundance 69.17%) and 65Cu
(atomic mass = 64.9278; abundance 30.83%). Calculate the atomic weight (average atomic mass) of copper.
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The Periodic Table and Molecules and Molecular Compounds
Read: pp. 49-54; Exercises: pp. 72,73: #38, 40, 43, 44, 47, 51
38.
Locate each of the following elements in the periodic table; indicate whether it is a metal, metalloid, or
non-metal; and give the name of the element:
a) Ca
b) Ti
c) Ga
d) Th
e) Pt
f) Se
g) Kr
40.
The elements of group 4A show an interesting change in properties with increasing period.
Give the name and chemical symbol of each element in the group, and label it as a nonmetal,
metalloid, or metal.
43.
Write the empirical formula corresponding to each of the following molecular formulas:
a) Al2Br6
b) C8H10
c) C4H8O2
d) P4O10
e) C6H4Cl2
f) B3N3H6
44.
Determine the molecular and empirical formulas of the following:
a) the organic solvent benzene, which has six carbon atoms and six hydrogen atoms;
b) the compound silicon tetrachloride, which has a silicon atom and four chlorine atoms and is used in the
manufacture of computer chips;
c) the reactive substance diborane, which has two boron atoms and six hydrogen atoms;
b) the sugar called glucose, which has six carbon atoms, twelve hydrogen atoms, and six oxygen atoms.
47. Write the molecular and structural formulas for the compounds represented by the molecular models on
p. 68.
51. Each of the following elements is capable of forming an ion in chemical reactions.
By referring to the periodic table, predict the charge of the most stable ion of each:
a) Mg
b) Al
c) K
d) Se
e) F
Ions and Ionic Compounds
Read: pp. 54-58; Exercises: p. 69: #53, 55, 59
53. Using the periodic table to guide you, predict the formula and name of the compound formed by the
following elements:
a) Ga and F
b) Li and H
c) Al and I
d) K and S
55. Predict the empirical formula for the ionic compound forms by
a) Ca2+ and Brb) K+ and CO32c) Al3+ and C2H3O2d) NH4+ and SO42e) Mg2+ and PO43-
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59. Predict whether each of the following compounds is molecular or ionic:
a. B2H6
b. CH3OH
c. LiNO3
d. Sc2O3
e. CsBr
f. NOCl
g. NF3
h. Ag2SO4
Naming Inorganic Compounds and Some Simple Organic Compounds
Read: pp. 59-67; Exercises: pp. 69, 70: #62, 63, 65, 67, 74
62. Selenium, an element required nutritionally in trace quantities, forms compounds analogous to sulfur. Name the
following ions:
a) SeO42b) Se2c) HSed) HSeO363. Give the names and charges of the cation and anion in each of the following compounds:
a) CaO
b) Na2SO4
c) KClO4
d) Fe(NO3)2
e) Cr(OH)3
65. Name the following ionic compounds:
a) MgO
b) AlCl3
c) Li3 PO4
d) Ba(ClO4)2
e) Cu(NO3)2
f) Fe(OH)2
g) Ca(C2H3O2)2
h) Cr2(CO3)3
i) K2CrO4
j) (NH4)2SO4
67. Give the chemical formula for each of the following ionic compounds:
a) aluminum hydroxide
b) potassium sulfate
c) copper (I) oxide
d) zinc nitrate
e) mercury(II) bromide
f) iron(III) carbonate
g) sodium hypobromite
69. Give the name or chemical formula, as appropriate, for each of the following acids:
a) HBrO3
b) HBr
c) H3PO4
d) hypochlorous acid
e) iodic acid
f) sulfurous acid
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73.
Write the chemical formula for each substance mentioned in the following word descriptions.
a) Zinc carbonate can be heated for form zinc oxide and carbon dioxide.
b) On treatment with hydrofluoric acid, silicon dioxide forms silicon tetrafluoride and water.
c) Sulfur dioxide reacts with water to form sulfurous acid.
d) The substance phosphorus trihydride, commonly called phosphine, is a toxic gas.
e) Perchloric acid reacts with cadmium to form cadmium (II) perchlorate.
f) Vanadium (III) bromide is a colored solid.
74. Assume that you encounter the following phrases in your reading.
What is the chemical formula for each substance mentioned?
a) Sodium hydrogen carbonate is used as a deodorant.
b) Calcium hypochlorite is used in some bleaching solutions.
c) Hydrogen cyanide is a very poisonous gas.
d) Magnesium hydroxide is used as a cathartic.
e) Tin(II) fluoride has been used as a fluoride additive in toothpastes.
f) When cadmium sulfide is treated with sulfuric acid, fumes of hydrogen sulfide are given off.
Chapter 3 “Stoichiometry: Calculations with Chemical Formulas and Equations” Assignments
Chemical Equations
Read: pp. 79-83; Exercises: pp. 109-110: #11, 13
11. Balance the following equations:
a) CO(g) + O2(g) Æ CO2(g)
b) N2O5(g) + H2O(l) Æ HNO3(aq)
c) CH4(g) + Cl2(g) Æ CCl4(l) + HCl(g)
d) Al4C3(s) + H2O(l) Æ Al(OH)3(s) + CH4(g)
e) C5H10O2(l) + O2(g) Æ CO2(g) + H2O(g)
f) Fe(OH)3(s) + H2SO4(aq) Æ Fe2(SO4)3(aq) + H2O(l)
g) Mg3N2(s) + H2SO4(aq) Æ MgSO4(aq) + (NH4)2SO4(aq)
13. Write balanced chemical equations to correspond to each of the following descriptions:
a) Solid calcium carbide, CaC2, reacts with water to form an aqueous solution of calcium hydroxide and
acetylene gas, C2H2.
b) When solid potassium chlorate is heated, it decomposes to form solid potassium chloride and oxygen gas.
c) Solid zinc metal reacts with sulfuric acid to form hydrogen gas and an aqueous solution of zinc sulfate.
d) When liquid phosphorus trichloride is added to water, it reacts to form aqueous phosphorous acid,
H3PO3(aq), and aqueous hydrochloric acid.
e) When hydrogen sulfide gas is passed over solid hot iron(III) hydroxide, the resultant reaction produces
solid iron(III) sulfide and gaseous water.
Some Simple Patterns of Chemical Reactivity
Read: pp. 84-87; Exercises: p. 110: #15, 17, 19
15. a) When the metallic element sodium combines with the nonmetallic element bromine, Br2(l), how can you
determine the chemical formula of the product? How do you know whether the product is a solid, liquid, or gas
at room temperature? Write the balanced chemical equation for the reaction.
b) When a hydrocarbon burns in air, what reactant besides the hydrocarbon is involved in the reaction?
What products are formed? Write a balanced chemical equation for the combustion of benzene, C6H6(l), in air.
17. Write a balanced chemical equation for the reaction that occurs when
a) solid magnesium reacts with chlorine gas;
b) nickel(III) hydroxide decomposes into nickel(II) oxide and water when heated;
c) the hydrocarbon styrene, C8H8(l), is combusted in air;
d) the gasoline additive MTBE (methyl tertiary-butyl ether), C5H12O(l), burns in air.
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19. Balance the following equations, and indicate whether they are combination, decomposition, or combustion
reactions:
a) Al(s) + Cl2(g) Æ AlCl3(s)
b) C2H4(g) + O2(g) Æ CO2(g) + H2O(g)
c) Li(s) + N2(g) Æ Li3N(s)
d) PbCO3(s) Æ PbO(s) + CO2(g)
e) C7H8O2(l) + O2(g) Æ CO2(g) + H2O(g)
20. Balance the following equations, and indicate whether they are combination, decomposition, or combustion
reactions:
a) C3H6(g) + O2(g) Æ CO2(g) + H2O(g)
b) NH4NO3(s) Æ N2O(g) + H2O(g)
c) C5H6O(l) + O2(g) Æ CO2(g) + H2O(g)
d) N2(g) + H2(g) Æ NH3(g)
e) K2O(s) + H2O(l) Æ KOH(aq)
Formula Weights
Read: pp. 87-89; Exercises: pp. 110,111: #21, 24
21. Determine the formula weights (molar masses) of each of the following compounds:
a) nitric acid, HNO3,
b) potassium permanganate, KMnO4,
c) calcium phosphate, Ca3(PO4)2,
d) quartz, SiO2,
e) gallium sulfide
f) chromium (III) sulfate
g) phosphorus trichloride
24.
Calculate the percentage by mass ox the indicated element in the following compounds:
a) carbon in acetylene, C2H2, a gas used in welding
b) hydrogen in ascorbic acid, HC6H7O6, also known as vitamin C
c) hydrogen in ammonium sulfate, (NH4)2SO4, a substance used as a nitrogen fertilizer
d) platinum in PtCl2(NH3)2, a chemotherapy agent called cisplatin
e) oxygen in the female sex hormone estradiol, C18H24O2
f) carbon in capsaicin, C18H27NO3, the compound that gives the hot taste to chili peppers
The Mole
Read: pp. 89-95; Exercises: pp. 111: #29
29. Without doing any detailed calculations (but using a periodic table to give atomic weights), rank the following
samples in order of increasing number of atoms: 0.50 mol H2O; 23 g Na; 6.0 x 1023 N2 molecules.
33. Calculate the following quantities:
a) mass, in grams, of 0.105 moles sucrose (C12H22O11)
b) moles of Zn(NO3)2 in 143.50 g of this substance
c) number of molecules in 1.0 x 10-6 mol CH3CH2OH
d) number of N atoms in 4.88 x 10-3 mol Al(NO3)3
35. a)
b)
c)
d)
What is the mass, in grams, of 2.50 x 10-3 mol of ammonium phosphate?
How many moles of chloride ions are in 0.2550 g of aluminum chloride?
What is the mass, in grams, of 7.70 x 1020 molecules of caffeine, C8H10N4O2?
What is the molar mass of cholesterol if 0.00105 mol weighs 0.406 g?
37. The molecular formula of allicin, the compound responsible for the characteristic smell of garlic, is C6H10OS2.
a) What is the molar mass of allicin?
b) How many moles of allicin are present in 5.00 mg of this substance?
c) How many molecules of allicin are in 5.00 mg of this substance?
d) How many S atoms are present in 5.00 mg of allicin?
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Empirical Formulas from Analysis
Read: pp. 95-98
Exercises: pp. 112: #39, 41, 43, 45, 47, 49
The last part of this section, including how to determine the formula of a hydrate, and how to use combustion analyses to
determine empirical formulas will be addressed early in the semester, probably Thurs., Aug. 20.
43. Give the empirical formula of each of the following compounds if a sample contains
a) 0.0130 mol C, 0.0390 mol H, and 0.0065 mol O
b) 11.66 g iron and 5.01 g oxygen
c) 40.0% C, 6.7% H, and 53.3% O by mass
45. Determine the empirical formulas of the compounds with the following compositions by mass:
a) 10.4% C, 27.8% S, and 61.7% Cl
b) 21.7% C, 9.6% O, and 68.7% F
c) 32,79% Na, 13.02% Al, and 54.19% F
47. What is the molecular formula of each of the following compounds?
a) empirical formula CH2, molar mass = 84 g/mol
b) empirical formula NH2Cl, molar mass = 51.5 g/mol
49. Determine the empirical and molecular formulas of each of the following substances:
a) Styrene, a compound substance used to make Styrofoam cups and insulation, 92.3% C and 7.7% H by mass and
has a molar mass of 104 g/mol;
b) caffeine, a stimulant found in coffee, contains 49.5% C, 5.15% H, 28.09% N, and 16.5% O by mass and has a
molar mass of 195 g/mol;
b) monosodium glutamate (MSG), a flavor enhancer in certain foods that contains 35.51% C, 4.77% H,
37.85% O, 8.29% N, and 13.60% Na, and has a molar mass of 169 g/mol.
Quantitative Information from Balanced Equations
Read: pp. 99-102; Exercises: p. 113: # 57, 58, 61,
55. Hydrofluoric acid, HF(aq), cannot be stored in glass bottles because compounds called silicates in the glass are
attacked by the HF(aq). Sodium silicate (Na2SiO3), for example, reacts as follows:
Na2SiO3 (s) + 8 HF(aq) Æ H2SiF6(aq) + 2 NaF(aq) + 3 H2O(l)
a) How many moles of HF are needed to react with 0.300 mol of Na2SiO3?
b) How many grams of NaF form when 0.500 mol of HF reacts with excess Na2SiO3?
c) How many grams of Na2SiO3 can react with 0.800 g of HF?
56. The fermentation of glucose (C6H12O6) produces ethyl alcohol (C2H5OH) and CO2:
C6H12O6 (aq) Æ 2 C2H5OH (aq) + 2 CO2 (aq)
a) How many moles of CO2 are produced when 0.400 mol of C6H12O6 reacts in this fashion?
b) How many grams of C6H12O6 are needed to form 7.50 g of C2H5OH?
c) How many grams of CO2 form when 7.50 g of C2H5OH are produced?
61. Aluminum sulfide reacts with water to form aluminum hydroxide and hydrogen sulfide.
a. Write the balanced chemical equation for this reaction.
b. How many grams of aluminum hydroxide are obtained from 10.5 g of aluminum sulfide?
64. The complete combustion of octane, C8H18, a component of gasoline, proceeds as follows:
2 C8H18(l) + 25 O2(g) Æ 16 CO2(g) + 18 H2O(g)
a) How many moles of O2 are needed to burn 1.25 mol of C8H18?
b) How many grams of O2 are needed to burn 10.0 g of C8H18?
c) Octane has a density of 0.692 g/mL at 20oC. How many grams of O2 are required to burn 1.00 gal of C8H18?
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