Chapter 12 1 for a solution containing only one solute dissolved in a solvent

Chapter 12 – Solutions

1. Which of the following concerning solutions is/are correct?

1.

The solvent in a mixture of gases is generally considered to be the substance

in greater amount.

2.

The solid dissolved in a solution is known as the solute.

3.

Solid solutions are called alloys.

A)

1 only

B)

2 only

C)

3 only

D)

1 and 2

E)

1, 2, and 3

2. Which of the following concerning solutions is/are correct?

1.

For a solution to form, the solvent and solute must be miscible.

2.

A solution may be homogeneous or heterogeneous.

3.

A colloid is a type of solution.

A)

1 only

B)

2 only

C)

3 only

D)

1 and 2

E)

1, 2, and 3

3. Suppose a small amount of a solid is added to water and, after a short time, all the solid has

dissolved. Which of the following statements is most likely to be true?

A)

The solution is supersaturated with solute.

B)

The solution is saturated with solute.

C)

The solution is unsaturated with solute.

D)

The solution is either unsaturated or supersaturated with solute.

E)

The solution is either saturated or supersaturated with solute.

Test Bank General Chemistry, 10th edition 2

4. Which of the following concerning solubility and the solution process is/are correct?

1.

In a saturated solution of a substance, a solution of the substance is in

equilibrium with the pure substance.

2.

Dissolution of a solute stops once saturation of a solvent is achieved.

3.

Solubility depends in part on the strength of solute-solute and solute-solvent

Van der Waals forces.

A)

1 only

B)

2 only

C)

3 only

D)

1 and 3

E)

1, 2, and 3

5. Which of the following concerning solubility and the solution process is/are correct?

1.

Both hydration energies and lattice energies depend on the magnitude of the

ion charges and the size of the ions.

2.

An initially nonhomogeneous mixture of two miscible liquids, given enough

time, will eventually form a solution as a result of random molecular motions.

3.

The dissolution of ionic compounds in water depends only on the hydration

energy of the ions.

A)

1 only

B)

2 only

C)

3 only

D)

1 and 2

E)

1, 2, and 3

6. Which of the following sets of conditions favors maximum solubility of solute in solvent?

A)

The intermolecular forces between solute and solvent molecules are much weaker

than the intermolecular forces between solute molecules, but much stronger than

the intermolecular forces between solvent molecules.

B)

The intermolecular forces between solute and solvent molecules are much stronger

than the intermolecular forces between solute molecules or the intermolecular

forces between solvent molecules.

C)

The intermolecular forces between solute and solvent molecules are much stronger

than the intermolecular forces between solvent molecules, but much weaker than

the intermolecular forces between solute molecules.

D)

The intermolecular forces between solute and solvent molecules are much stronger

than the intermolecular forces between solute molecules, but much weaker than the

intermolecular forces between solvent molecules.

E)

The intermolecular forces between solute and solvent molecules are much weaker

than the intermolecular forces between solute molecules or the intermolecular

forces between solvent molecules.

7. In general, which of the following type(s) of solid(s) would exhibit the greatest solubility in

a nonpolar solvent?

A)

network covalent

B)

nonpolar molecular

C)

ionic

D)

metallic

E)

polar molecular

8. Which of the following gases is least soluble in water?

A)

CO2

B)

SO3

C)

NH3

D)

N2

E)

HCl

9. Which of the following pure liquids is the best solvent for sodium fluoride?

A)

CCl4(l)

B)

C2Cl6(l)

C)

HCl(l)

D)

BCl3(l)

E)

PCl5(l)

Test Bank General Chemistry, 10th edition 4

10. Which of the following pure liquids is the best solvent for carbon disulfide?

A)

C6H6(l)

B)

NH3(l)

C)

CH3OH(l)

D)

H2O(l)

E)

HBr(l)

11. Which of the following compounds is least soluble in water?

A)

CH3CH2CH2NH2

B)

CH3CH2CH2F

C)

CH3CH(OH)CH3

D)

CH3CH2COOH

E)

CH3CH2NHCH3

12. The solubility of 1-hexanol in water is 0.60 g per 100 g of water at 25°C. What is the

maximum amount of 1-hexanol that will dissolve in 5.3 g of water at 25°C?

A)

0.032 g

B)

0.11 g

C)

0.60 g

D)

3.2 g

E)

0.0011 g

13. Which of the following sets of conditions favors maximum solubility of an ionic solute in

water?

A)

The enthalpy of hydration of the cation should be equal to the enthalpy of

hydration of the anion, regardless of the magnitude of the lattice energy.

B)

The magnitude of the lattice energy should be small, and the enthalpy of hydration

of the ions should be large.

C)

The magnitude of the lattice energy should be small, and the enthalpy of hydration

of the ions should be small.

D)

The magnitude of the lattice energy should be large, and the enthalpy of hydration

of the ions should be small.

E)

The magnitude of the lattice energy should be large, and the enthalpy of hydration

of the ions should be large.

14. Which of the following favor(s) the solubility of an ionic solid in a liquid solvent?

A)

a small magnitude of the lattice energy of the solute

B)

a large magnitude of the solvation energy of the ions

C)

a large polarity of the solvent

D)

all of the above

E)

none of the above

15. Which of the following statements best describes what happens when a small amount of

solid rubidium bromide is dissolved in water?

A)

The heat from the warm water melts the solid, making it a liquid.

B)

Nothing happens, because rubidium bromide is insoluble in water.

C)

The solid RbBr breaks apart into separate Rb and Br atoms by interacting with the

water molecules.

D)

The water molecules surround each ion in the solid RbBr, separating the Rb ions

from the Br ions.

E)

The solid undergoes a chemical change by reacting with the water.

16. Which of the following correctly states the relationship between the solubility of a substance

in water and temperature?

A)

The solubility of a substance in water increases as the temperature rises, especially

for gases.

B)

The solubility of a substance in water decreases as the temperature lowers,

especially for gases.

C)

The relationship between the solubility of a substance in water and temperature

cannot be accurately predicted, especially for ionic solids.

D)

The solubility of a substance in water decreases as the temperature rises, especially

for ionic solids.

E)

Two of these are correct.

Test Bank General Chemistry, 10th edition 6

17. Which of the following concerning the effects of temperature and pressure on solubility

is/are correct?

1.

All gases become more soluble in a liquid at a fixed pressure when the

temperature of the liquid is increased.

2.

The dissolution of an ionic compound in water may be exothermic or

endothermic, depending on the initial temperature of the solution.

3.

The solubility of a liquid in water generally is significantly effected by

pressure changes of the system.

A)

1 only

B)

2 only

C)

3 only

D)

1 and 2

E)

none

18. Consider the following gas-aqueous liquid equilibrium for a closed system at a constant

temperature.

O2(g)

O2(aq)

What is the effect on the equilibrium composition of the liquid when the partial pressure of

O2 gas above the liquid is increased?

A)

The amount of O2 dissolved in the liquid increases.

B)

The amount of O2 dissolved in the liquid decreases.

C)

The amount of O2 dissolved in the liquid does not change.

D)

Not enough information is provided to answer the question.

E)

Either A or B.

19. Consider the following gas-liquid equilibrium for an aqueous system at a constant partial

pressure of N2.

N2(g)

N2(aq)

What is the effect on the equilibrium composition of the liquid when the temperature of the

liquid is increased?

A)

The amount of N2 dissolved in the liquid increases.

B)

The amount of N2 dissolved in the liquid decreases.

C)

The amount of N2 dissolved in the liquid does not change.

D)

Not enough information is provided to answer the question.

E)

Either A or B could occur.

20. Which of the following affect(s) the solubility of gases in solvents?

1.

the nature of the gas

2.

the nature of the solvent

3.

the temperature of the solvent

A)

1 only

B)

2 only

C)

3 only

D)

1 and 2

E)

1, 2, and 3

21. How does the solubility of a gas in a solvent depend on pressure and temperature?

A)

Increasing the partial pressure of the gas while increasing the temperature

increases the solubility of the gas.

B)

Decreasing the partial pressure of the gas while decreasing the temperature

increases the solubility of the gas.

C)

Increasing the partial pressure of the gas while decreasing the temperature

increases the solubility of the gas.

D)

Decreasing the partial pressure of the gas while increasing the temperature

increases the solubility of the gas.

E)

Gas solubility is unaffected by pressure or temperature.

22. Which of the following is a correct statement of Henry’s law?

A)

The concentration of a gas in solution is directly proportional to the mole fraction

of solvent.

B)

The concentration of a gas in solution is inversely proportional to temperature.

C)

The concentration of a gas in solution is independent of pressure.

D)

The concentration of a gas in a solution is inversely proportional to pressure.

E)

none of these

23. The solubility of a gas in a liquid can always be increased by

A)

decreasing the pressure of the gas above the solvent.

B)

increasing the pressure of the gas above the solvent.

C)

increasing the temperature of the solvent.

D)

decreasing the polarity of the solvent.

E)

decreasing the temperature of the gas above the solvent.

24. At a particular temperature the solubility of O2 in water is 0.590 g/L at an oxygen pressure

of around 14.7 atm. What is the Henry’s law constant for O2 (in units of L · atm/mol)?

A)

4.01  10-2

B)

7.97  102

C)

2.71  10-1

D)

1.25  10-3

E)

None of the above are within 5% of the correct answer.

Test Bank General Chemistry, 10th edition 9

25. According to the National Institute of Standards webbook, the Henry’s Law constant for N2

gas is 0.00060 mol/kgbar at 25C What is the Henry’s law constant in units of mol/kgatm?

(1 bar = 0.9869 atm; 1 atm = 760 mmHg)

A)

6.1 10−4

mol/kgatm

B)

8.0 10−7

mol/kgatm

C)

4.6 10−1

mol/kgatm

D)

1.6 103

mol/kgatm

E)

1.3 106

mol/kgatm

26. Henry’s Law constant is 0.00060 mol/kgbar and 0.0013 mol/kgbar for N2 and O2

respectively at 25C. What pressure of O2 is required to achieve the same solubility as 0.616

bar of N2?

A)

0.28 bar

B)

1.3 bar

C)

4.8 10−7

bar

D)

1.3 10−6

bar

E)

3.5 bar

27. If the solubility of O2 at 0.360 bar and 25C is 15.0 g/100 g H2O, what is the solubility of O2

at a pressure of 1.72 bar and 25C?

A)

71.7 g/100 g H2O

B)

24.2 g/100 g H2O

C)

0.319 g/100 g H2O

D)

0.0140 g/100 g H2O

E)

3.14 g/100 g H2O

28. Which of the following is not a colligative property?

A)

boiling-point elevation

B)

osmotic pressure

C)

gas solubility

D)

freezing-point lowering

E)

vapor-pressure lowering

29. As the number of solute particles in a given volume of solution increases,

A)

the boiling point will increase and the vapor pressure will increase.

B)

the freezing point will decrease and the vapor pressure will decrease.

C)

the freezing point will increase and the vapor pressure will increase.

D)

the boiling point will decrease and the vapor pressure will decrease.

E)

the osmotic pressure will decrease and the lattice energy will increase.

30. The molarity of a solution is defined as the

A)

moles of solute per liter of solvent.

B)

grams of solute per kilogram of solvent.

C)

grams of solute per liter of solution.

D)

moles of solute per liter of solution.

E)

moles of solute per kilogram of solvent.

31. The molarity of a solution is defined as the

A)

moles of solute per liter of solvent.

B)

moles of solute per kilogram of solution.

C)

moles of solute per mole of solution.

D)

moles of solute per kilogram of solvent.

E)

moles of solute per liter of solution.

32. The molality of a solution is defined as

A)

moles of solute per liter of solution.

B)

the gram molecular weight of solute per kilogram of solvent.

C)

moles of solute per kilogram of solvent.

D)

grams of solute per liter of solution.

E)

moles of solute per kilogram of solution.

33. Which of the following concerning the topic of concentration is/are correct?

1.

A concentrated solution of hydrochloric acid has a molarity of 12 M. This

means that 12 moles of HCl are dissolved in 1.0 L of water.

2.

The molality of a solution is unaffected by changes in temperature, even

though the total volume of the solution may change significantly.

3.

When calculating a mass percent, the “mass of solution” is equal to the sum of

the masses of all solution components.

A)

1 only

B)

2 only

C)

3 only

D)

2 and 3

E)

1, 2, and 3

34. Which of the following concerning the topic of concentration is/are correct?

1.

A 5.0 molal HCl solution consists of 5.5 moles HCl dissolved in 1.0 kg of

solution.

2.

The mass percent and mole percent of a particular component in a solution are

identical.

3.

The mole fraction of a component in a solution may never be greater than 1.

A)

1 only

B)

2 only

C)

3 only

D)

1 and 2

E)

none of the above

35. What mass of an aqueous 22.9% sodium chloride solution contains 99.5 g of water?

A)

129 g

B)

29.6 g

C)

0.500 g

D)

22.8 g

E)

99.5 g

36. What is the mass of H2SO4 in a 49.5-cm3 sample of concentrated sulfuric acid that has a

density of 1.84 g/cm3 and consists of 98.3% H2SO4?

A)

48.7 g

B)

89.5 g

C)

3.65 g

D)

1.81 g

E)

26.4 g

37. A concentrated sulfuric acid solution is 65.0% H2SO4 by mass and has a density of 1.55

g/mL at 20°C. What is the mass of 3.00 L of the concentrated sulfuric acid solution?

A)

1.95 kg

B)

3.00 kg

C)

7.15 kg

D)

1.26 kg

E)

4.65 kg

38. A concentrated potassium hydroxide solution is 45.0% KOH by mass and has a density of

1.44 g/mL at 25°C. What is the mass of KOH per L of solution?

A)

648 g KOH/L soln

B)

0.00144 g KOH/L soln

C)

313 g KOH/L soln

D)

0.320 g KOH/L soln

E)

3.13 g KOH/L soln

39. A concentrated phosphoric acid solution is 85.5% H3PO4 by mass and has a density of 1.69

g/mL at 25°C. What is the molarity of H3PO4?

A)

14.7 M

B)

0.166 M

C)

5.16 M

D)

19.4 M

E)

0.0516 M

Test Bank General Chemistry, 10th edition 13

40. A concentrated perchloric acid solution has a density of 1.67 g/mL at 25°C and is 11.7 M.

What is the percent by mass of HClO4 in the solution?

A)

70.4% HClO4 by mass

B)

0.702% HClO4 by mass

C)

1.42% HClO4 by mass

D)

0.699% HClO4 by mass

E)

60.2% HClO4 by mass

41. What is the mass percent of an aqueous sodium hydroxide solution in which the mole

fraction of NaOH is 0.231? The density of the solution is 1.4339 g/mL.

A)

40.0%

B)

6.21%

C)

68.9%

D)

33.1%

E)

6.44%

42. What is the mass percent of an aqueous sodium hydroxide solution in which the molarity of

NaOH is 4.37 M? The density of the solution is 1.1655 g/mL.

A)

0.267%

B)

15.0%

C)

5.09%

D)

1.53%

E)

68.9%

43. What is the mass percent of an aqueous sodium hydroxide solution in which the molality of

NaOH is 25.0 m? The density of the solution is 1.5290 g/mL.

A)

0.0612%

B)

68.9%

C)

1.76%

D)

50.0%

E)

0.654%

44. The mass of a 12.0% (by mass) solution is 8.82 g. The density of the solution is

1.120 g/mL. What is the mass of the water in this solution?

A)

7.76 g

B)

10 g

C)

1.19 g

D)

0.00774 g

E)

8.69 g

45. The volume of a 14.4% (by mass) solution is 67.0 mL. The density of the solution is

1.072 g/mL. What is the mass of the solution?

A)

71.8 g

B)

62.5 g

C)

1030 g

D)

103 g

E)

10.3 g

46. The volume of a 15.8% (by mass) solution is 146.4 mL. The density of the solution is

1.084 g/mL. What is the mass of solute in this solution?

A)

159 g

B)

25.1 g

C)

1004 g

D)

21.3 g

E)

134 g

47. What is the molarity of a 20.0% by mass hydrochloric acid solution? The density of the

solution is 1.0980 g/mL.

A)

6.86 M

B)

0.200 M

C)

5.68 M

D)

6.02 M

E)

0.0220 M

48. What mass of a 26.0% by mass glucose, C6H12O6, solution contains 42.0 g of glucose?

A)

46.8 g

B)

162 g

C)

10.9 g

D)

60.7 g

E)

42.0 g

49. What is the percent Na2CO3 by mass in a 1.54 molal aqueous solution?

A)

0.132%

B)

14.0%

C)

99.4%

D)

16.3%

E)

15.4%

50. What mass of a solution labeled 6.3% sucrose (C12H22O11, 342 g/mol) by mass contains

15.0 g of sucrose?

A)

3.4 g

B)

39 g

C)

240 g

D)

0.28 g

E)

95 g

51. A 12.0% sucrose solution by mass has a density of 1.05 g/cm3. What mass of sucrose is

present in a 30.0-mL sample of this solution?

A)

3.78 g

B)

3.43 g

C)

0.126 g

D)

263 g

E)

3.60 g

52. How many moles of urea (60. g/mol) must be dissolved in 77.6 g of water to give a 3.5 m

solution?

A)

2.1  102 mol

B)

3.5 mol

C)

0.0035 mol

D)

0.27 mol

E)

7.7  102 mol

53. If 12.7 g of naphthalene, C10H8, is dissolved in 104.6 g of chloroform, CHCl3, what is the

molality of the solution?

A)

0.0992 m

B)

14.5 m

C)

0.949 m

D)

0.108 m

E)

0.113 m

54. What is the molality of a solution prepared by dissolving 0.244 mol of chloroform, CHCl3,

in 456 g of toluene, C6H5CH3?

A)

0.0642 m

B)

0.0469 m

C)

0.535 m

D)

0.0492 m

E)

1.113 m

55. What is the molality of a solution prepared by dissolving 2.57 g of urea, NH2CONH2, in

57.6 g of water?

A)

0.0427 m

B)

0.0446 m

C)

0.0132 m

D)

0.743 m

E)

0.000711 m

56. A 3.140 molal solution of NaCl is prepared. How many grams of NaCl are present in a

sample containing 2.191 kg of water?

A)

243.9 g

B)

402.1 g

C)

117.7 g

D)

688.0 g

E)

none of these

57. What is the molality of a solution that contains 77.7 g of 1,4-dichlorobenzene (C6H4Cl2) in

445 mL of carbon tetrachloride (CCl4)? The density of CCl4 is 1.60 g/mL.

A)

0.183 m

B)

0.743 m

C)

0.175 m

D)

0.109 m

E)

1.90 m

58. What is the molality of ethanol, C2H5OH, in an aqueous solution that is 51.0% ethanol by

mass?

A)

1.04 m

B)

0.0226 m

C)

22.6 m

D)

0.719 m

E)

53.4 m

Test Bank General Chemistry, 10th edition 18

59. A concentrated potassium hydroxide solution is 45.0% KOH by mass and has a density of

1.44 g/mL at 25°C. The remainder of material is solvent. What is the molality of KOH in

the solution?

A)

14.6 m

B)

8.02 m

C)

5.53 m

D)

686 m

E)

1.02 m

60. What is the molality of a 20.0% by mass hydrochloric acid solution? The density of the

solution is 1.0980 g/mL.

A)

0.0220 m

B)

6.86 m

C)

0.200 m

D)

5.68 m

E)

6.02 m

61. What is the molality of a solution that contains 8.16 g of glucose, C6H12O6, in 252.5 g of

water?

A)

0.180 m

B)

0.0453 m

C)

0.00322 m

D)

0.0114 m

E)

0.0323 m

62. For a solution containing only one solute dissolved in a solvent, we can calculate the mole

fraction of the solvent directly, given only

A)

the molar mass of the solute.

B)

the density of the solution.

C)

the molar mass of the solvent.

D)

the mole fraction of the solute.

E)

the molarity of the solution.