General Chemistry: Atoms First, 2e (McMurry and Fay)
Chapter 11 Solutions and Their Properties
11.1 Multiple Choice Questions
1) Which of the following mixtures have components which can be separated by filtration?
A) colloids
B) solutions
C) suspensions
D) all of the above
2) Stainless steel is an example of a ________ solution.
A) gas/solid
B) liquid/liquid
C) solid/liquid
D) solid/solid
3) In most liquid solutions, the component present in the larger amount is called the
A) dispersed medium.
B) emulsifying agent.
C) solute.
D) solvent.
4) The rubbing alcohol sold in drug stores often is composed of 70% isopropyl alcohol and 30%
water. In this solution
A) isopropyl alcohol is the solvent.
B) water is the solvent.
C) both water and isopropyl alcohol are solvents.
D) neither water nor isopropyl alcohol is a solvent.
5) Which is not a solution?
A) brass
B) fog
C) hydrochloric acid
D) wine
6) 10 grams of table sugar (sucrose, ) is dropped into a beaker containing 100 grams
of water and stirred until a clear liquid is visible and all of the sugar has dissolved. This process
may be described as
A) the formation of a heterogeneous mixture.
B) the formation of a homogeneous solution.
C) sublimation.
D) the formation of a chemical compound.
7) For a liquid solution made by dissolving a solid or a gas in a liquid, the
A) liquid is the solute.
B) liquid is the solvent.
C) solute is the component present in the greatest amount.
D) solvent is the component present in the greatest amount.
8) Iodine, I2(s), is more soluble in dichloromethane, CH2Cl2(l), than in water because
A) both iodine and dichloromethane have strong ion-dipole interactions.
B) the dipole-dipole forces in dichloromethane are much stronger than the dispersion forces in
iodine.
C) the intermolecular forces are similar in both iodine and dichloromethane.
D) iodine is polar and dichloromethane has a large number of hydrogen bonds.
9) Which of the following pairs of liquids are likely to be miscible?
A) OH and O
B) and O
C) and O
D) and O
10) Which of the following pairs of liquids are likely to be not miscible?
A) and O
B) OH and O
C) C and
D) and
11) For which case would ΔHsoln be expected to be negative?
A) if solute-solute interactions are much greater than solvent-solvent and solute-solvent
interactions
B) if solvent-solvent interactions are much greater than solute-solvent and solute-solute
interactions
C) if solute-solvent interactions are much greater than solvent-solvent and solute-solute
interactions
D) if solute-solvent interactions are the same as solvent-solvent and solute-solute interactions
12) KBr does not dissolve well in nonpolar solvents because
A) solute-solute interactions are much larger than solvent-solvent or solute-solvent interactions.
B) solvent-solvent interactions are much larger than solute-solvent or solute-solute interactions.
C) solute-solvent interactions are much larger than solvent-solvent or solute-solute interactions.
D) solute-solvent interactions are similar to solvent-solvent and solute-solute interactions.
13) Commercial cold packs often contain solid NH4NO3 and a pouch of water. The temperature
of the pack drops as the NH4NO3 dissolves in water. Therefore, for the dissolving of NH4NO3
in water,
A) ΔHsoln is negative and ΔSsoln may be negative or positive.
B) ΔHsoln is negative and ΔSsoln is positive.
C) ΔHsoln is positive and ΔSsoln may be negative or positive.
D) ΔHsoln is positive and ΔSsoln is positive.
14) When a particular solid begins to dissolve in water, the temperature rises dramatically. For
the dissolving of this solid in pure water
A) ΔHsoln is always negative and ΔSsoln may be negative or positive.
B) ΔHsoln is always negative and ΔSsoln is always positive.
C) ΔHsoln is always positive and ΔSsoln may be negative or positive.
D) ΔHsoln is always positive and ΔSsoln is always positive.
15) In the process of dissolving ionic compounds, the cations and anions are separated from the
crystal lattice and surrounded by an ordered shell of solvent molecules. If the solvent is water,
the dissolved ions are said to be
A) halogenated.
B) homogenized.
C) hybridized.
D) hydrated.
16) One reason ionic compounds do not dissolve well in nonpolar solvents is that
A) ion-dipole interactions are too large for effective solvation to occur.
B) ion-solvent interactions are not strong enough to solvate the ions in solution.
C) not all cations and anions have the same magnitude of charge and therefore do not form
neutral ion pairs.
D) there are no forces of attraction between ions and nonpolar molecules.
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17) Which cation in each set is expected to have the larger (more negative) hydration energy?
I Mg2+ or Ba2+
II K+ or Al3+
A) Mg2+ in set I and K+ in set II
B) Mg2+ in set I and Al3+ in set II
C) Ba2+ in set I and K+ in set II
D) Ba2+ in set I and Al3+ in set II
18) Which cation in each set would be expected to have the larger (more negative) hydration
energy?
I Fe2+ or Fe3+
II Li+ or NH4+
A) Fe2+ in set I and Li+ in set II
B) Fe2+ in set I and NH4+ in set II
C) Fe3+ in set I and Li+ in set II
D) Fe3+ in set I and NH4+ in set II
19) Although there are exceptions, which is most likely to be true for the dissolving of a solid in
a liquid?
A) ΔHsoln is positive.
B) ΔHsoln is negative.
C) ΔSsoln is positive.
D) ΔSsoln is negative.
20) When two similar liquids mix to form a solution, the entropy of solution (ΔSsoln) is expected
to be
A) negative.
B) zero.
C) positive.
D) negative at low temperatures but positive at high temperatures.
21) When an ionic solute dissolves in water to form an unsaturated solution, the free energy
change (ΔGsoln) is
A) negative.
B) zero.
C) positive.
D) either A or C, depending on the ionic compound
22) The change in the Gibbs free energy for dissolving more solute in a supersaturated solution is
A) negative.
B) zero.
C) positive.
D) positive at low temperatures and negative at high temperatures.
23) The change in the Gibbs free energy for dissolving solute in a saturated solution is
A) negative.
B) zero.
C) positive.
D) positive at low temperatures and negative at high temperatures.
24) For the process of dissolving a solid in a liquid, which of the following statements is true?
A) ΔHsoln is always negative and ΔSsoln is usually positive.
B) ΔHsoln is always positive and ΔSsoln is usually negative.
C) ΔHsoln is either positive or negative and ΔSsoln is usually positive.
D) ΔHsoln is either positive or negative and ΔSsoln is usually negative.
25) Most gases become less soluble in water as the temperature increases. What can be
concluded about the signs of and in this case?
A) ΔHsoln is negative and ΔSsoln is negative.
B) ΔHsoln is negative and ΔSsoln is positive.
C) ΔHsoln is positive and ΔSsoln is negative.
D) ΔHsoln is positive and ΔSsoln is positive.
26) Arrange the following compounds in order of their expected increasing solubility in water:
KCl, CH3CH2-O-CH2CH3, CH3CH2CH2CH2-OH, CH3CH2CH2CH2CH3.
A) CH3CH2CH2CH2CH3 < KCl < CH3CH2-O-CH2CH3 < CH3CH2CH2CH2–OH
B) KCl < CH3CH2-O-CH2CH3 < CH3CH2CH2CH2-OH < CH3CH2CH2CH2CH3
C) CH3CH2CH2CH2CH3 < CH3CH2-O-CH2CH3 < KCl < CH3CH2CH2CH2–OH
D) CH3CH2CH2CH2CH3 < CH3CH2-O-CH2CH3 < CH3CH2CH2CH2-OH < KCl
27) Which of the following should most favor the solubility of an ionic solid in water?
A) a low lattice energy for the solid and a low hydration energy for its ions
B) a low lattice energy for the solid and a high hydration energy for its ions
C) a high lattice energy for the solid and a low hydration energy for its ions
D) a high lattice energy for the solid and a high hydration energy for its ions
28) Which should be least soluble in water?
A)
B)
C)
D)
29) What are the major solute-solvent interactions created when KBr dissolves in water?
A) dipole-dipole
B) dispersion
C) hydrogen bonding
D) ion-dipole
30) What are the major solute-solvent interactions created when HOCH2CH2OH dissolves in
water?
A) dipole-dipole
B) dispersion
C) hydrogen bonding
D) ion-dipole
31) Substances with high lattice energies tend to be less soluble than substances with low lattice
energies. On that basis predict the relative aqueous solubility at 20°C, from highest to lowest, of
the following ionic compounds: Ce2(SO4)3, K2SO4, KBr, NaCl.
A) Ce2(SO4)3 > K2SO4 > KBr > NaCl
B) Ce2(SO4)3 > K2SO4 > NaCl > KBr
C) KBr > NaCl > K2SO4 > Ce2(SO4)3
D) NaCl > KBr > K2SO4 > Ce2(SO4)3
32) Molarity is defined as moles of solute per
A) kilogram of solvent.
B) liter of solution.
C) mole of solvent.
D) total moles present.
33) Molality is defined as moles of solute per
A) kilogram of solvent.
B) liter of solution.
C) mole of solvent.
D) total moles present.
34) Which concentration becomes smaller as the temperature is increased from 20°C to 80°C?
A) mass %
B) molality
C) molarity
D) mole fraction
35) What is the mole fraction of ethanol in a solution made by dissolving 14.6 g of ethanol,
C2H5OH, in 53.6 g of water?
A) 0.0964
B) 0.106
C) 0.214
D) 0.272
36) What is the molality of ethanol in a solution made by dissolving 14.6 g of ethanol, C2H5OH,
in 53.6 g of water?
A) 0.00591 m
B) 0.272 m
C) 5.91 m
D) 272 m
37) What is the mole fraction of I2 in a solution made by dissolving 27.8 g of I2 in 245 g of
hexane, C6H14?
A) 0.0371
B) 0.0385
C) 0.0715
D) 0.0770
38) What is the mole fraction of oxygen in a gas mixture that is 22% oxygen and 78% nitrogen
by volume?
A) 0.20
B) 0.22
C) 0.25
D) 0.28
39) A solution is prepared by dissolving 17.75 g sulfuric acid, H2SO4, in enough water to make
100.0 mL of solution. If the density of the solution is 1.1094 g/mL, what is the mole fraction
H2SO4 in the solution?
A) 0.0181
B) 0.0338
C) 0.0350
D) 19.0
40) A solution is prepared by dissolving 17.75 g sulfuric acid, H2SO4, in enough water to make
100.0 mL of solution. If the density of the solution is 1.1094 g/mL, what is the molarity?
A) 0.1775 M H2SO4
B) 0.1810 M H2SO4
C) 1.810 M H2SO4
D) 1.940 M H2SO4
41) A solution is prepared by dissolving 17.75 g sulfuric acid, H2SO4, in enough water to make
100.0 mL of solution. If the density of the solution is 1.1094 g/mL, what is the molality?
A) 0.1775 m H2SO4
B) 0.1810 m H2SO4
C) 1.810 m H2SO4
D) 1.940 m H2SO4
42) A solution is prepared by dissolving 17.75 g sulfuric acid, H2SO4, in enough water to make
exactly 100.0 mL of solution. If the density of the solution is 1.1094 g/mL, what is the mass %
H2SO4 in the solution?
A) 16.00%
B) 18.00%
C) 19.00%
D) 84.00%
43) A solution is prepared by dissolving 171 g of CdCl2 in enough water to make 250.0 mL of
solution. If the density of the solution is 1.556 g/mL, what is the molarity of the solution?
A) 0.440 M
B) 0.684 M
C) 0.933 M
D) 3.73 M
44) A solution is prepared by dissolving 171 g of CdCl2 in enough water to make exactly 250.0
mL of solution. If the density of the solution is 1.556 g/mL, what is the mass percent of CdCl2 in
the solution?
A) 7.17%
B) 44.0%
C) 56.0%
D) 68.4%
45) What is the mass percent of vitamin C in a solution made by dissolving 1.30 g of vitamin C,
C6H8O6, in 55.0 g of water?
A) 0.195%
B) 0.242%
C) 2.31%
D) 2.36%
46) What is the mass percent of a caffeine solution made by dissolving 4.35 g of caffeine,
C8H10N4O2, in 75 g of benzene, C6H6?
A) 0.055%
B) 0.058%
C) 5.5%
D) 5.8%
47) What volume of 0.716 M KBr solution is needed to provide 10.5 g of KBr?
A) 7.52 mL
B) 14.7 mL
C) 63.2 mL
D) 123 mL
48) What volume of 3.00 M CH3OH solution is needed to provide 0.270 mol of CH3OH?
A) 1.23 mL
B) 11.1 mL
C) 90.0 mL
D) 810 mL
49) How much water must be added to 42.0 g of CaCl2 to produce a solution that is 35.0 mass %
CaCl2?
A) 56.7 g
B) 78.0 g
C) 83.3 g
D) 120 g
50) To make a 2.0 M solution, one could take 2.00 moles of solute and add
A) 1.00 L of solvent.
B) 1.00 kg of solvent.
C) enough solvent to make 1.00 L of solution.
D) enough solvent to make 1.00 kg of solution.
51) To make a 2.00 m solution, one could take 2.00 moles of solute and add
A) 1.00 L of solvent.
B) 1.00 kg of solvent.
C) enough solvent to make 1.00 L of solution.
D) enough solvent to make 1.00 kg of solution.
52) What molality of pentane is obtained by dissolving 5.0 g pentane, C5H12, in 245.0 g hexane,
C6H14?
A) 0.020 m
B) 0.024 m
C) 0.28 m
D) 20. m
53) A solution is 2.25% by mass NaHCO3. How many grams of NaHCO3 are in 450.0 g of
solution?
A) 0.500 g
B) 10.1 g
C) 200 g
D) 225 g
54) How many grams of KBr are required to make 650. mL of a 0.115 M KBr solution?
A) 0.628 g
B) 5.65 g
C) 8.90 g
D) 74.8 g
55) What is the molality of a glucose solution prepared by dissolving 18.0 g of glucose,
C6H12O6, in 125.9 g of water?
A) 7.94 × 10-4 m
B) 0.143 m
C) 0.695 m
D) 0.794 m
56) Aqueous solutions of 30% (by mass) hydrogen peroxide, H2O2, are used to oxidize metals
or organic molecules in chemical reactions. Given that the density of the solution is 1.11 g/mL,
calculate the molarity.
A) 0.794 M
B) 6.78 M
C) 9.79 M
D) 12.6 M
57) Aqueous solutions of 30.0% (by mass) hydrogen peroxide, H2O2, are used to oxidize metals
or organic molecules in chemical reactions. Calculate the molality of this solution.
A) 0.974 m
B) 6.78 m
C) 9.79 m
D) 12.6 m
58) Sodium hydroxide is available commercially as a 50.0% by weight aqueous solution. The
density of the solution is 1.53 g/mL. Calculate the molarity of this sodium hydroxide solution.
A) 0.450 M
B) 19.1 M
C) 25.0 M
D) 125. M
59) Sodium hydroxide is available commercially as a 50.0% by weight aqueous solution.
Calculate the molality of this sodium hydroxide solution.
A) 0.450 m
B) 19.1 m
C) 25.0 m
D) 125. m
60) A 1.30 M solution of CaCl2 in water has a density of 1.11 g/mL. What is the molality?
A) 1.17 m CaCl2
B) 1.25 m CaCl2
C) 1.35 m CaCl2
D) 1.44 m CaCl2
61) A 3.17 m solution of CaCl2 in water has a density of 1.24 g/mL. What is the molarity?
A) 2.56 M CaCl2
B) 2.91 M CaCl2
C) 3.50 M CaCl2
D) 3.93 M CaCl2
62) A 2.00 M solution of CaCl2 in water has a density of 1.17 g/mL. What is the mole fraction of
CaCl2?
A) 0.0348
B) 0.0360
C) 0.0366
D) 0.0380
63) A solution of LiCl in water has XLiCl = 0.0500. What is the molality?
A) 2.60 m LiCl
B) 2.77 m LiCl
C) 2.92 m LiCl
D) 5.26 m LiCl
64) A solution of LiCl in water is 18.0 mass % LiCl. What is the mole fraction of LiCl?
A) 0.0853
B) 0.0933
C) 0.425
D) 4.56
65) At 25.0°C, a solution has a concentration of 3.179 M and a density of 1.260 g/mL. The
density of the solution at 50.0°C is 1.249 g/mL. What is the molarity of the solution at 50.0°C?
A) 2.545 M
B) 3.151 M
C) 3.179 M
D) 3.230 M
66) A saturated solution is defined as
A) a concentrated solution.
B) a solution that is in equilibrium with pure solvent.
C) a solution than is in equilibrium with undissolved solute.
D) a solution that is in equilibrium with both pure solvent and undissolved solute.
67) Which of the following does not affect the solubility of a solute in a given solvent?
A) polarity of the solute
B) polarity of the solvent
C) rate of stirring
D) temperature of the solvent and solute
68) Which of the following statements is true for a supersaturated solution?
A) The solute in the solution is at equilibrium with undissolved solute.
B) The solution contains more than the equilibrium amount of solute.
C) The solution is stable and the solute will not precipitate.
D) A supersaturated solution is more than 50% solute by mass.
69) In general, as the temperature increases, the solubility of gases in water ________ and the
solubility of most solids in water ________.
A) decreases, decreases
B) decreases, increases
C) increases, decreases
D) increases, increases
70) The solubility of gaseous solutes in liquid solvents is greater when the
A) external pressure over the solution is increased.
B) external pressure is decreased.
C) partial pressure of the gas above the solution is increased.
D) partial pressure of the solvent is increased.
71) In which case should CO2(g) be more soluble in water?
A) The total pressure is 5 atm and the partial pressure of CO2 is 1 atm.
B) The total pressure is 3 atm and the partial pressure of CO2 is 2 atm.
C) The total pressure is 1 atm and the partial pressure of CO2 is 0.03 atm.
D) The total pressure is 1 atm and the partial pressure of CO2 is 0.5 atm.
72) The Henry’s Law constant of methyl bromide, CH3Br, is k = 0.159 mol/(L ∙ atm) at 25°C.
What is the solubility of methyl bromide in water at 25°C and at a partial pressure of 250. mm
Hg?
A) 0.0523 mol/L
B) 0.329 mol/L
C) 0.483 mol/L
D) 39.8 mol/L
73) The solubility of argon in water at 25°C is 0.0150 mol/L. What is the Henry’s Law constant
for argon if the partial pressure of argon in air is 0.00934 atm?
A) 1.40 × 10-4 mol/(L ∙ atm)
B) 0.623 mol/(L ∙ atm)
C) 1.61 mol/(L ∙ atm)
D) 4.10 mol/(L ∙ atm)
74) Which of the following is not an application of colligative properties?
A) adding silver to mercury to lower the vapor pressure of mercury
B) desalinating sea water by reverse osmosis
C) melting snow by application of salt
D) reduced boiling points of pure liquids at increased altitudes
75) A solution is prepared by dissolving 40.0 g of sucrose, C12H22O11, in 250. g of water at
25°C. What is the vapor pressure of the solution if the vapor pressure of water at 25°C is 23.76
mm Hg?
A) 0.198 mm Hg
B) 20.5 mm Hg
C) 23.6 mm Hg
D) 24.0 mm Hg
76) A KCl solution is prepared by dissolving 40.0 g KCl in 250.0 g of water at 25°C. What is the
vapor pressure of the solution if the vapor pressure of water at 25°C is 23.76 mm Hg?
A) 20.5 mm Hg
B) 22.1 mm Hg
C) 22.9 mm Hg
D) 25.5 mm Hg
77) At a given temperature the vapor pressures of benzene and toluene are 183 mm Hg and 59.2
mm Hg, respectively. Calculate the total vapor pressure over a solution of benzene and toluene
with Xbenzene = 0.600.
A) 110 mm Hg
B) 121 mm Hg
C) 133 mm Hg
D) 242 mm Hg
78) At a given temperature the vapor pressures of benzene and toluene are 183 mm Hg and 59.2
mm Hg, respectively. Calculate the mole fraction of benzene in the vapor phase over a solution
of benzene and toluene with Xbenzene = 0.600.
A) 0.600
B) 0.678
C) 0.756
D) 0.823
79) How many grams of sucrose, C12H22O11, must be added to 500. g of water at 100°C to
change the vapor pressure to 752 mm Hg?
A) 0.295 g
B) 5.32 g
C) 10.6 g
D) 101 g