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Chapter 12—Liquids and Solids--REVIEW
MULTIPLE CHOICE
3. The particles in both gases and liquids
a. consist only of atoms.
b. can change positions with other particles.
c. vibrate in fixed positions.
d. are packed closely together.
4. The compressibility of a liquid is generally
a. less than that of a gas.
b. more than that of a gas.
c. equal to that of a gas.
d. zero.
5. The intermolecular forces between particles are
a. less effective in solids than in liquids.
c. equally effective in gases and in liquids.
b. more effective in gases than in solids.
d. more effective in liquids than in gases.
6. The lower mobility of particles in a liquid compared with those in a gas results in the liquid being
a. less disordered.
c. colder.
b. lower in density.
d. higher in energy.
9. What is vaporization?
a. the process by which a liquid changes to a gas
b. the process by which a solid changes to a gas
c. both a and b
d. neither a nor b
11. What causes particles in a liquid to escape into a gas state?
a. high kinetic energy
c. surface tension
b. a freezing temperature
d. the combining of liquids
13. A solid forms when the average energy of a substance's particles
a. increases.
c. decreases then increases.
b. decreases.
d. creates a disorderly arrangement.
14. Which of the following statements about freezing is NOT correct?
a. All liquids freeze.
c. Not all liquids freeze.
b. Water freezes at 0ºC.
d. Some liquids freeze at room temperature.
16. Particles within a solid
a. do not move.
b. vibrate weakly about fixed positions.
c. vibrate energetically.
d. exchange positions easily.
18. The energy level of the particles in a solid is
a. higher than the energy of the particles in a gas.
b. high enough to allow the particles to interchange with other particles.
c. higher than the energy of the particles in a liquid.
d. lower than the energy of the particles in liquids and gases.
20. The intermolecular forces between particles in a solid are
a. weaker than those in a gas.
b. too weak to hold the particles in fixed positions.
c. stronger than those in a liquid.
d. of different types than those in a liquid.
23. In general, most substances are
a. least dense in the liquid state.
b. more dense as gases than as solids.
c. less dense as solids than as liquids.
d. most dense in the solid state.
24. The rate of diffusion in solids is very low because the
a. particles are not free to move about.
c. attractive forces are weak.
b. surfaces of solids usually contact gases.
d. melting points are high.
26. Which of the following properties do solids share with liquids?
a. fluidity
c. definite volume
b. definite shape
d. slow rate of diffusion
29. When heated, a pure crystalline solid will
a. gradually soften before it melts.
b. melt over a wide temperature range.
c. exhibit a definite melting temperature.
d. melt at a temperature slightly above its freezing temperature.
44. Whenever a liquid changes to a vapor, it
a. absorbs heat energy from its surroundings.
b. is in equilibrium with its vapor.
c. is boiling.
d. is condensing.
46. If the rate of evaporation from the surface of a liquid exceeds the rate of condensation,
a. the system is in equilibrium.
b. the liquid is boiling.
c. heat energy is no longer available.
d. the concentration of the vapor is increasing.
47. If the temperature and surface area of a liquid remain constant,
a. the liquid is not in equilibrium with its vapor.
b. no further evaporation occurs.
c. the rate of evaporation remains constant.
d. the rate of condensation is greater than the rate of evaporation.
48. Molecules at the surface of a liquid can enter the vapor phase only if
a. equilibrium has not been reached.
b. the concentration of the vapor is zero.
c. their energy is high enough to overcome the attractive forces in the liquid.
d. condensation is not occurring.
55. If the temperature of a liquid-vapor system at equilibrium increases, the new equilibrium condition will
a. have a lower concentration of vapor.
b. have an increased vapor pressure.
c. not have equal rates of condensation and evaporation.
d. be larger in volume.
65. What is the process of a substance changing from a solid to a vapor without passing through the liquid
phase?
a. condensation
c. sublimation
b. evaporation
d. vaporization
67. Why would a camper near the top of Mt. Everest find that water boils at less than 100ºC?
a. There is greater atmospheric pressure than at sea level.
b. The flames are hotter at that elevation.
c. There is less atmospheric pressure than at sea level.
d. The atmosphere has less moisture.
68. Glycerol boils at a slightly higher temperature than does water. This reveals that glycerol's attractive
forces are
a. nonexistent.
c. the same as those of water.
b. weaker than those of water.
d. stronger than those of water.
70. During boiling, the temperature of a liquid
a. remains constant.
b. increases.
c. decreases.
d. approaches the standard boiling point.
71. During the process of freezing, a liquid
a. loses kinetic energy.
b. loses potential energy.
c. gains potential energy.
d. gains kinetic energy.
75. The triple point of a substance is the temperature and pressure conditions at which
a. density is greatest.
b. states of a substance coexist at equilibrium.
c. equilibrium cannot occur.
d. kinetic energy is at a minimum.
79. What does the dotted line in the figure above represent?
a. the number of moles of liquid present
c. standard pressure
b. the temperature of all three liquids
d. boiling temperature
82. Why are water molecules polar?
a. They contain two kinds of atoms.
b. The electrons in the covalent bonds spend more time closer to the oxygen nucleus.
c. The hydrogen bonds are weak.
d. They have covalent bonds.
83. Why is ice less dense than liquid water?
a. The molecules in liquid water can crowd together more compactly than in ice.
b. Liquid water's energy level is lower than that of ice.
c. Liquid water molecules are farther apart than the molecules in ice.
d. Liquid water has fewer chemical impurities than ice has.
85. If the water molecules were nonpolar, it is likely that
a. water would be a solid at room temperature.
b. water would be flammable.
c. water would be a gas at room temperature.
d. the hydrogen bonding would be stronger.
87. What is the freezing point of water at standard pressure?
a. –10ºC
c. 4ºC
b. 0ºC
d. 32ºC
88. How does the molar heat of fusion of ice compare with the molar heat of fusion of other solids?
a. It is about the same.
b. It is relatively small.
c. It is relatively large.
d. It is about the same as that of colorless solids.
91. At about what temperature does water reach its maximum density?
a. 0ºC
c. 4ºC
b. 2ºC
d. 6ºC
92. What is the mass of 1 mL of water at its temperature of maximum density?
a. 1 mg
c. 1 g
b. 1.5 mg
d. 1.5 g
93. When water is warmed from its freezing temperature to its temperature of maximum density, it
a. contracts.
c. maintains a constant volume.
b. expands.
d. increases in weight.
94. Why doesn't water in lakes and ponds of temperate climates freeze solid during the winter and kill nearly
all the living things it contains?
a. Water is colorless.
b. Ice floats.
c. The molar heat of fusion of ice is relatively low.
d. Water contracts as it freezes.
95. What is the characteristic of water that makes steam useful for household heating systems?
a. high molar heat of vaporization
c. high density
b. low molar heat of fusion
d. low boiling point
96. The molar heat of vaporization of water is 40.79 kJ at 100ºC. What is the heat of vaporization of 1 g of
water?
a. 40.79 J
c. 500. J
b. 80.3 J
d. 2.26 kJ
97. The molar heat of fusion for water is 6.008 kJ/mol. How much energy would be required to melt 94.0 g of
ice?
a. 0.869 kJ
c. 31.3 kJ
b. 81.7 kJ
d. 282. kJ
100. The standard molar heat of vaporization for water is 40.79 kJ/mol. What mass of steam is required to
release 500. kJ of heat energy upon condensation?
a. 221 g
c. 1130 g
b. 325 g
d. 1660 g
SHORT ANSWER
1. Explain how evaporation occurs.
2. How are vaporization and evaporation related?
3. How is a solid formed?