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AP Chemistry Review Assignment
Brown and LeMay: Chemistry the Central Science, 11th edition
Chapter 1 “Introduction: Matter and Measurement” Assignments
Classification and Properties of Matter
13. 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 Heterogeneous mixture
b) seawater
Homogeneous mixture unless there are undissolved particles such as sand,
then heterogeneous
c) magnesium Element
d) gasoline
Homogeneous mixture
17. 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?
.A – compound
B – cannot be determined, C - compound
19. 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. Red – Physical, Green Chemical
Units of Measurement
26. Use the appropriate metric prefixes to write the following measurements without use of
exponents:
a) 2.3 x 10-2 L 23 mL
b) 4.7 x 10-4 g .47 mg
c) 1.85 x 10-12 m 1.85 pm
27.
a) A sample of carbon tetrachloroethylen, a liquid once used in dry cleaning that is being
phased out because of its potential to cause cancer, has a mass of 40.55 g and a volume of
25.0 mL at 25oC. What is its density at this temperature? Will carbon
tetrachloroethylene float on water? 1.62 g/mL, it will sink in water
b) Carbon dioxide is a gas at room temperature and pressure. However, carbon dioxide can be
put under pressure to become a “supercritical fluid” that is a much safer dry-cleaning agent
than tetrachloroethylene. At a certain pressure, the density of supercritical carbon dioxide is
0.469 g/cm3. What is the mass of a 25.0 mL sample of supercritical CO2 at this pressure?
11.7 grams
Uncertainty in Measurement
35. Indicate which of the following are exact numbers: b, d, and e
a)
the mass of a 3 x 5 index card
b)
the number of ounces in a pound
c)
the volume of a cup of coffee
d)
the number of inches in a mile
e)
the number of microseconds in a week
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37. What is the number of significant figures in each of the following measured quantities:
a) 601 kg 3
b) 0.054 s 2
c) 6.3050 cm 5
d) 0.0105 L 3
e) 7.0500 x 10-3 m3 5
41. Carry out the following operations, and express the answers with the appropriate numbers of
significant figures:
a) 14.3505 + 2.65 = 16.97
b) 952.7 - 140.7389 = 812.0
c) (3.29 x 104)(0.2501) = 8230
d) 0.0588/0.677 = 0.869
Dimensional Analysis
50. Perform the following conversions:
a) 5.00 days to s 216,000 s
b) 0.0550 mi to m 88.5 m
c) $1.89/gal to dollars per liter $0.499
54. a) If an electric car is capable of going 225 km on a single charge, how many charges will it
need to travel from Seattle, Washington to San Diego, California, a distance of 1257mi, assuming
that the trip begins with a full charge? 3.47 charges
b) If a migrating loon flies at an average speed of 14 m/s, what is its average speed in mi/hr? 31
mi/hr
Chapter 2 “Atoms, Molecules and Ions” Assignments
The Atomic Theory and The Discovery of Atomic Structure
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? The path of the charged particle bends
because it is repelled by the negatively charged plate and attracted to the positively charged
plate.
b) What is the sign of the electrical charge on the particle that bends up? negative
c) As the charge on the plates is increased, would you expect the bending to increase,
decrease, or stay the same? Like charges repel and opposite charges attract, so the sign of
the electrical charge on the particle is negative.
d) 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? The greater the
magnitude of the charges, the greater the electrostatic repulsion or attraction. As the charge
on the plates is increased, the bending will increase.
11. How does Dalton’s atomic theory account for the fact that when 1.000 g of water is decomposed
into its elements, 0.111 g of hydrogen and 0889 g of oxygen are obtained regardless of the source of
the water? The Law of Definite Composition states that a particular compound always has the same
proportion of each element to the every other element.
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18. 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 Calculated Charge (C)
A
1.60 x 10-19
B
3.15 x 10-19
C
4.81 x 10-19
D
6.31 x 10-19
a) What is the significance of the fact that the droplets carried different charges? The droplets
carry different total charges because there may be 1,2,3 or more electrons on the droplet.
b) What conclusion can the student draw from these data regarding the charge of the electron?
The electronic charge is likely to be the lowest common factor in all the observed charges.
c) What value (and to how many significant figures) should she report for the electronic
charge? The average of the apparent electrical charges is 1.59 x 10-19 C
The Modern View of Atomic Structure and Atomic Weights
22. 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 very little of the volume of an atom;
b) Every atom of a given element has the same number of protons; True
c) The number of electrons in an atom equals the number of protons in the atom;
d) The protons in the nucleus of the helium atom are held together by a force called the strong
nuclear force. True
29. Fill in the gaps in the following table assuming each column represents a neutral atom:
Symbol
79
55
112
222
207
Br
Mn
Cd
Rn
Pb
Protons
Neutrons
Electrons
Mass number
35
25
48
86
82
44
30
64
136
125
35
25
48
86
82
79
55
112
222
207
33. a) What isotope is used as the standard in establishing the atomic mass scale? Carbon - 12
b) The atomic weight of boron is reported as 10.81, yet no atom of boron has the mass of
10.81 amu. Explain. Atomic weights are really average atomic masses, the sum of the mass of
each naturally occurring isotope of an element times its fractional abundance. Each B atom will
have the mass of one of the naturally occurring isotopes, while the atomic weight is an average
value.
35. 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.
63.55 amu
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The Periodic Table and Molecules and Molecular Compounds
42. 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) Li Lithium (metal)
b) Sc Scandium (metal)
c) Ge Germanium (metalloid)
d) Yb Ytterbium (metal)
e) Mn Manganese (metal)
44. 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. C, carbon, nonmetal; Si, silicon, metalloid; Ge, germanium, metalloid; Sn, tin,
metal; Pb, lead, metal
49. Write the empirical formula corresponding to each of the following molecular formulas:
a) Al2Br6 AlBr3
b) C8H10 C4H5
c) C4H8O2 C2H4O2
50. Determine the molecular and empirical formulas of the following:
a) the organic solvent benzene, which has six carbon atoms and six hydrogen atoms; C6H6, CH
b) the compound silicon tetrachloride, which has a silicon atom and four chlorine atoms and is
used in the manufacture of computer chips; SiCl4 for both
57. 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) Mg2+
b) Al3+
c) K1+
d) S2e) F1Ions and Ionic Compounds
59. Using the periodic table to guide you, predict the formula and name of the compound formed by
the following elements:
a) Ga and F GaF3, gallium (III) fluoride
b) Li and H LiF, lithium hydride
c) Al and I AlI3, Aluminum iodide
61. Predict the chemical formula for the ionic compound formed by
a) Ca2+ and Br- CaBr2
b) K+ and CO32- K2CO3
c) Al3+ and C2H3O2- Al(C2H3O2)3
65. Predict whether each of the following compounds is molecular or ionic:
a. B2H6
b. CH3OH
c. LiNO3
d. Sc2O3
Naming Inorganic Compounds and Some Simple Organic Compounds
69. Give the names and charges of the cation and anion in each of the following compounds:
a) CaO calcium, 2+; oxide 2b) KClO4 potassium 1+; Chloride 1c) Fe(NO3)2 iron, 2+; nitrate 174. Give the chemical formulas for each of the following ionic compounds:
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a)
b)
c)
d)
sodium phosphate Na3PO4
zinc nitrate Zn(NO3)2
barium bromate Ba(BrO3)2
iron(II) perchlorate Fe(ClO4)2
75. Give the name or chemical formula, as appropriate, for each of the following acids:
a) HBrO3 bromic acid
b) HBr hydrobromic acid
c) H3PO4 phosphoric acid
d) hypochlorous acid HClO
e) iodic acid HIO3
79. 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. Zn(CO3)2, ZnO, CO2
b) On treatment with hydrofluoric acid, silicon dioxide forms silicon tetrafluoride and water.
HF, SiO2, SiF4, H2O
c) Sulfur dioxide reacts with water to form sulfurous acid. SO2, H2O, H2SO3
80. 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. NaHCO3
b) Calcium hypochlorite is used in some bleaching solutions. Ca(ClO)2
c) Hydrogen cyanide is a very poisonous gas. HCN
81. a) What is a hydrocarbon? A hydrocarbon is a compound composed of only hydrogen and
carbon. b) Pentane is the alkane with a chain of five carbon atoms. Write a structural formula for this
compound and determine its molecular and empirical formulas. C5H12
84. a) What do ethane and ethanol have in common? Ethane and Ethanol both have 2 Carbons (ethprefix) B) How does 1-propanol differ from propane? 1-Propanol has an –OH (alcohol group) attached to
the chain of 3 carbons that propane does not have.
Chapter 3 “Stoichiometry: Calculations with Chemical Formulas and Equations” Assignments
Chemical Equations
11. Balance the following equations:
a) 2CO(g) + O2(g)  2CO2(g)
b) N2O5(g) + H2O(l)  2HNO3(aq)
c) CH4(g) + 4Cl2(g)  CCl4(l) + 4HCl(g)
15. 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. CaC2 + 2H2 O  Ca(OH)2 + C2H2
b) When solid potassium chlorate is heated, it decomposes to form solid potassium chloride
and oxygen gas.
2KClO3(s)  2KCl (s) + 3O2
c) Solid zinc metal reacts with sulfuric acid to form hydrogen gas and an aqueous solution of
zinc sulfate.
Zn(s) + H2SO4(aq)  H2 + ZnSO4(aq)
Some Simple Patterns of Chemical Reactivity
17. 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
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a solid, liquid, or gas at room temperature? Write the balanced chemical equation for the reaction.
You need to look at the charges for both ions and write a formula that is neutral as the compound.
Since ionic compounds are all solid at room temperature, and sodium bromide is an ionic compound,
you can assume that it is a solid. 2Na(s) + Br2(l)  2NaBr (s)
18. When a compound containing C, H, and O is complete combusted in air, what reactant besides the
hydrocarbon is involved in the reaction? Oxygen gas What products are formed? Carbon dioxide and
water
19. Write a balanced chemical equation for the reaction that occurs when
a) Mg reacts with Cl2 ; Mg(s) + Cl2(g)  MgCl2(s)
b) Barium carbonate decomposes into barium oxide and carbon dioxide when heated;
BaCO3  BaO + CO2
c) the hydrocarbon styrene, C8H8(l), is combusted in air; C8H8 + 10O2  8CO2 + 4H2O
21. Balance the following equations, and indicate whether they are combination, decomposition, or
combustion reactions:
a) C2H4(g) + 3O2(g)  2CO2(g) + 2H2O(g) Combustion
b) NH4NO3(s)  N2O(s) + 2H2O (g)
Decomposition
e) C5H6O(l) + 6O2(g)  5CO2(g) + 3H2O(g) Combustion
Formula Weights
23. Determine the formula weights (molar masses) of each of the following compounds:
a) nitric acid, HNO3, 63.0 g/mol
b) potassium permanganate, KMnO4, 158.0 g/mol
c) calcium phosphate, Ca3(PO4)2, 270.2 g/mol
25. Calculate the percentage by mass of oxygen in the following compounds:
a) morphine, C17H19NO3 61 % Oxygen
b) codeine, C18H21NO3 19% Oxygen
c) cocaine, C17H21NO4 27 % Oxygen
The Mole
31. 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.
Na, H2O , N2
35. Calculate the following quantities:
a) mass, in grams, of 0.105 moles sucrose (C12H22O11) 35.9 g sucrose
b) moles of Zn(NO3)2 in 143.50 g of this substance 0.7576 mol Zinc Nitrate
c) number of molecules in 1.0 x 10-6 mol CH3CH2OH 6.0 x 1017 Ethanol molecules
d) number of N atoms in 4.88 x 10-3 mol Al(NO3)3
39. The molecular formula of allicin, the compound responsible for the characteristic smell of garlic,
is C6H10OS2.
a) What is the molar mass of allicin? C6H10OS2
b) How many moles of allicin are present in 5.00 mg of this substance? 3.08 x 10-5 moles
c) How many molecules of allicin are in 5.00 mg of this substance? 1.86 x 1019 molecules
Empirical Formulas from Analysis
45. 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 C2H6O
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b) 11.66 g iron and 5.01 g oxygen Fe2O3
c) 40.0% C, 6.7% H, and 53.3% O by mass CH2O
47. Determine the empirical formulas of the compounds with the following compositions by mass:
a) 10.4% C, 27.8% S, and 61.7% Cl CSCl2
b) 21.7% C, 9.6% O, and 68.7% F C3OF6
51. What is the molecular formula of each of the following compounds?
a) empirical formula CH2, molar mass = 84 g/mol C6H12
b) empirical formula NH2Cl, molar mass = 51.5 g/mol Same!
53. 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; CH, C8H8
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; C4H5N2O; C8H10N4O2
Quantitative Information from Balanced Equations
61. 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)  H2SiF6(aq) + 2 NaF(aq) + 3 H2O(l)
a) How many moles of HF are needed to react with 0.300 mol of Na2SiO3? 2.40 mol HF
b) How many grams of NaF form when 0.500 mol of HF reacts with excess Na2SiO3? 5.25 g NaF
c) How many grams of Na2SiO3 can react with 0.800 g of HF? 0.610 g Na2SiO3
65. Aluminum sulfide reacts with water to form aluminum hydroxide and hydrogen sulfide.
a) Write the balanced chemical equation for this reaction. Al2S3(s) + 6H2O(l) 
2Al(OH)3(s) + 3H2S(g)
b) How many grams of aluminum hydroxide are obtained from 14.2 g of aluminum sulfide?
14.7 g Al(OH)3
68. The complete combustion of octane, C8H18, a component of gasoline, proceeds as follows:
2 C8H18(l) + 25 O2(g)  16 CO2(g) + 18 H2O(g)
a) How many moles of O2 are needed to burn 1.25 mol of C8H18?15.6 moles O2
b) How many grams of O2 are needed to burn 10.0 g of C8H18? 35.0 g O2
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?
9.18 x 103g O2
Limiting Reactants: Theoretical Yields
74. A bottling plant as 126,515 bottles with a capacity of 355 mL, 108,500 caps, and 48,775 L of
beverage. (a) How many bottles can be filled and capped? 1.085 x 105 bottles can be filled and
capped (b) How much of each item is left over? 0 caps remain and 18,015 bottles remain and
10,257 L of beverage remain (c) Which component limits the production? The # of caps limit
production
78. Aluminum hydroxide reacts with sulfuric acid as follows:
2Al(OH)3 (s) + H2SO4 (aq) --> Al2(SO4)3(aq) + 6H2O (l)
Which reagent is the limiting reactant when 0.500 mol Al(OH)3 0.500 mol H2SO4 are allowed to
react? Al(OH)3 How many moles of Al2(SO4)3 can form under these conditions? 0.250 mol
Al2(SO4)3 can form How many moles of the excess reactant remain after the completion of the
reaction? 0.250 mol H2SO4 remain
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80. One of the steps in the commercial process for converting ammonia to nitric acid is the conversion
of NH3 to NO:
4 NH3 (g) + 5 O2 (g) --> 4 NO (g) + 6 H2O (g)
In a certain experiment, 2.00 g of NH3 reacts with 2.50 g of O2. (a) Which is the limiting reactant?
O2 (b) How many grams of NO and of H2O form? 1.88 g of NO and 1.69 g water formed (c) How
many grams of the excess reactant remain after the limiting reactant is completely consumed?
0.944 g NH3 remain (d) Show that your calculations in parts (b) and (c) are consistent with the law
of conservation of mass. Mass products = 1.88 g NO + 1.69 g H2O + 0.944 g NH3 remaining =
4.51 g products
Mass reactants = 2.00 g NH3 + 2.50 g O2 = 4.50 g. reactants
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