Chemistry for Changing Times, 14e (Hill/McCreary)
Chapter 6 Gases, Liquids, Solids, and Intermolecular Forces
6.1 Multiple Choice Questions
1) Which state of matter is characterized by having molecules close together, but moving randomly?
A) gas
B) liquid
C) solid
D) all of these
2) Which state of matter is characterized by having molecules far apart and moving randomly?
A) gas
B) liquid
C) solid
D) all of these
3) Which state of matter is characterized by having molecules close together and confined in their
movement?
A) gas
B) liquid
C) solid
D) all of these
4) The temperature at which a liquid becomes a solid is called the
A) melting point.
B) decomposition point.
C) boiling point.
D) condensation point.
5) The temperature at which a liquid becomes a gas is called the
A) melting point.
B) boiling point.
C) sublimation point.
D) decomposition point.
6) The process by which a liquid is converted to a gas is called
A) sublimation.
B) condensation.
C) melting.
D) vaporization.
7) The process by which a gas is converted to a liquid is called
A) condensation.
B) ionization.
C) sublimation.
D) vaporization.
8) The process by which a liquid is converted to a solid is called
A) condensation.
B) freezing.
C) liquefaction.
D) vaporization.
9) The process by which a solid is converted to a gas is called
A) liquefaction.
B) vaporization.
C) sublimation.
D) condensation.
10) Matter is more likely to exist in the ________ state as the temperature is lowered.
A) solid
B) liquid
C) gaseous
D) elemental
11) Matter is more likely to exist in the ________ state as the pressure is increased.
A) solid
B) liquid
C) gaseous
D) elemental
12) The temperature at which a solid melts is the melting point of the solid. The melting point is an
indication of the intermolecular forces that hold the solid together. Water melts at 0°C. Table sugar
(sucrose) melts at 285°C. Gallium, Ga, melts at 30°C. Which one of the following ranks the
intermolecular forces in these solids from the strongest to the weakest?
A) Ga > water > sucrose
B) sucrose > Ga > water
C) water > sucrose > Ga
D) Ga > sucrose > water
13) The temperature at which a liquid boils is the boiling point of the liquid. The boiling point is an
indication of the intermolecular forces that hold the matter in the liquid state. Water, H2O, boils at 100°C.
Ethanol, C2H6O boils at 78°C. Ammonia, NH3, boils at -33°C. Which one of the following ranks the
intermolecular forces in these liquids from the strongest to the weakest?
A) Water > Ammonia > Ethanol
B) Ammonia > Ethanol > Water
C) Ethanol > Water > Ammonia
D) Water > Ethanol > Ammonia
14) The temperature at which a solid melts is the melting point of the solid. The melting point is an
indication of the intermolecular forces that hold a solid together. Aluminum melts at 660°C. Gold melts
at 1064°C. Lead melts at 328°C. Which one of the following ranks the intermolecular forces in these solid
elements from the strongest to the weakest?
A) Au > Al > Pb
B) Al > Au > Pb
C) Pb > Au > Al
D) Au > Pb > Al
15) The degree of order of matter is directly proportional to the cohesive forces that hold the matter
together. In other words, the more organized the state of matter, the stronger the “glue” that holds it
together. Which of the following ranks these cohesive forces from the state with the strongest to that with
the weakest cohesive forces?
A) gas > liquid > solid
B) liquid > solid > gas
C) solid > liquid > gas
D) solid = gas = liquid
16) List the disadvantage of using supercritical carbon dioxide.
A) Precision electrical parts are degreased.
B) Oils are isolated from the plant source.
C) Special equipment is needed for the high temperature and high pressure.
D) Coffee is decaffeinated.
17) Matter is more likely to exist in the ________ state as the temperature is raised.
A) solid
B) liquid
C) gas
D) elemental
18) Matter is more likely to exist in the ________ state as the pressure is reduced.
A) solid
B) liquid
C) gas
D) elemental
19) Which of the following ranks the three states of matter from most to least ordered?
A) gas > liquid > solid
B) gas > solid > liquid
C) solid > gas > liquid
D) solid > liquid > gas
20) The process by which a gas is converted to a liquid is called
A) condensation.
B) melting.
C) vaporization.
D) sublimation.
21) A liquid
A) has a definite volume and a definite shape.
B) has a definite shape but no definite volume.
C) has a definite volume but no definite shape.
D) is readily compressible.
22) A gas
A) has a definite shape but no definite volume.
B) has a definite volume but no definite shape.
C) has both a definite shape and a definite volume.
D) has no definite shape and no definite volume.
23) Which of the following processes involves the removal of energy (heat)?
A) condensation
B) melting
C) sublimation
D) vaporization
24) All of the following solvents are no longer widely used as solvents for nonpolar organic compounds
EXCEPT
A) benzene.
B) methylene chloride.
C) supercritical carbon dioxide (scCO2).
D) perchloroethylene.
25) All of the following statements about scCO2 are correct EXCEPT
A) It can dissolve substances, just as liquids can.
B) It flows rapidly, just as gases do.
C) It causes cancer.
D) It can make processes occur more rapidly.
26) Ionic compounds have strong forces between particles. This means that generally ionic compounds
are ________ at room temperature.
A) solids
B) liquids
C) gases
D) covalently bonded
27) Which of the following compounds will have the highest melting point?
A) SO2
B) BaF2
C) N2H4
D) SCl6
28) Which of the following is NOT a property of an ionic compound? Ionic compounds generally
A) dissolve in water.
B) form solutions that conduct electricity well.
C) have melting points lower than those of molecular compounds.
D) require more energy to change from the liquid to the gaseous state.
29) Methanol
A) can dissolve in water and will not conduct electricity.
B) can dissolve in water and will conduct electricity.
C) does not dissolve in water and will not conduct electricity.
D) does not dissolve in water and will conduct electricity.
30) Which of the following properties are NOT a characteristic of ionic compounds?
A) They have low boiling points.
B) They are composed of a metal and a nonmetal.
C) They tend to be solids at room temperature.
D) They may be soluble in water.
31) For which of the following is hydrogen bonding NOT a factor?
A) H2O
B) NH3
C) CI4
D) CH3OH
32) What type of forces exist between bromine molecules in liquid bromine?
A) hydrogen bonding
B) dipole forces
C) dispersion forces
D) ionic bonds
33) Liquid hydrogen is used as one part of the booster fuel in the space shuttle. What type of forces exist
between hydrogen molecules in liquid hydrogen?
A) hydrogen bonding
B) dipole forces
C) dispersion forces
D) ionic bonds
34) Water is a liquid at room temperature while methane is a gas. Which statement compares the
intermolecular forces in these molecules correctly?
A) The intermolecular forces in methane are stronger than those in water.
B) The intermolecular forces in water are stronger than those in methane.
C) Both water and methane have the same intermolecular forces.
D) There is not enough information to compare these forces.
35) What is the predominant intermolecular force between HCl molecules?
A) ionic bonds
B) hydrogen bonds
C) dipole forces
D) dispersion forces
36) Which of the following is the weakest?
A) dipole forces
B) dispersion forces
C) hydrogen bonds
D) ionic bonds
37) Ethane has the formula CH3CH3. What is the predominant intermolecular force between ethane
molecules?
A) dipole forces
B) dispersion forces
C) hydrogen bonds
D) ionic bonds
38) Methanol has the formula CH3OH. What is the predominant intermolecular force between methanol
molecules?
A) dipole forces
B) dispersion forces
C) hydrogen bonds
D) ionic bonds
39) When an ionic compound dissolves in water,
A) the negative ends of water molecules surround the negative ions.
B) the positive ends of water molecules surround the positive ions.
C) the negative ends of water molecules surround the positive ions.
D) the negative ends of water molecules surround both the negative and the positive ions.
40) The attraction between an ion and water molecules is
A) ion-ion interaction.
B) ion-dipole interaction.
C) hydrogen bonding.
D) dispersion interaction.
41) In a solution, the solvent is
A) present in larger amount than the solute is.
B) dissolved in the solute.
C) always water.
D) always nonpolar.
42) Which of the following is NOT a postulate of the kinetic-molecular theory?
A) Molecules of a gas move rapidly and in straight lines.
B) The molecules in a gas are tiny compared to the distance between them.
C) The molecules of a gas are strongly attracted to each other.
D) If two molecules collide with each other, the total energy of the molecules before the collision is the
same as their total energy after the collision.
43) According to the kinetic-molecular theory, gas molecules have
A) strong interactions between molecules.
B) weak interactions between molecules.
C) little distance between molecules.
D) less energy than molecules of a solid.
44) The kinetic-molecular theory of gases assumes which of the following?
A) There are weak but significant interactions between gas molecules.
B) The total amount of energy will change when gas molecules collide.
C) The average kinetic energy of gas molecules will increase when you lower the temperature of the gas.
D) Gas molecules move constantly and in straight lines.
45) The volume of one mole of krypton at STP is
A) 12.4 liters.
B) 22.4 liters.
C) 12.4 gallons.
D) 6.02 × 1023 liters.
46) At STP, 22.4 liters of nitrogen gas, N2, will have a mass of
A) 14.0 g.
B) 22.4 g.
C) 28.0 g.
D) 35.0 g.
47) At STP, 22.4 liters of krypton gas, Kr, will have a mass of
A) 20.9 g.
B) 41.9 g.
C) 83.8 g.
D) 167 g.
48) At STP, 1 mole of oxygen gas, O2, will have a mass of
A) 16.0 g.
B) 22.4 g.
C) 28.0 g.
D) 32.0 g.
49) The density of Xe at STP is
A) 5.86 g/L.
B) 16.4 g/L.
C) 32.8 g/L.
D) 48.2 g/L.
50) The density of O2 gas at STP is
A) 0.714 g/L.
B) 1.00 g/L.
C) 1.43 g/L.
D) 1.69 g/L.
51) For a given amount of gas at a constant temperature, the volume of gas varies inversely with its
pressure is a statement of ________ Law.
A) Charles’s
B) Avogadro’s
C) Boyle’s
D) Curie’s
52) A gas is enclosed in a cylinder fitted with a piston. The volume of the gas is 5.00 L at 0.500 atm
pressure. The piston is moved to increase the volume to 3.00 L. Which of the following is a reasonable
value for the pressure of the gas at the greater volume?
A) 0.300 atm
B) 0.833 atm
C) 30.0 atm
D) 0.0333 atm
53) A gas is enclosed in a 15.0 L tank at 600 mm Hg pressure. Which of the following is a reasonable value
for the pressure when the gas is pumped into a 3.00 L vessel?
A) 1000 mm Hg
B) 120 mm Hg
C) 3000 mm Hg
D) 1200 mm Hg
54) A gas is enclosed in a 10.0 L tank at 1200 mm Hg pressure. Which of the following is a reasonable
value for the pressure when the gas is pumped into a 5.00 L vessel?
A) 2400 mm Hg
B) 600 mm Hg
C) 24 mm Hg
D) 42 mm Hg
55) The statement that the volume of a fixed amount of a gas at a constant pressure is directly
proportional to its absolute temperature is known as ________ Law.
A) Charles’s
B) Boyle’s
C) Gay-Lussac’s
D) Avogadro’s
56) A balloon is inflated outdoors on a cold day in North Dakota at a temperature of –35°C to a volume of
3.0 L. The pressure remains constant. What is the volume of the balloon indoors at a temperature of 25°C?
A) 2.4 L
B) 3.8 L
C) 3.2 L
D) 2.1 L
57) A sample of gas at a temperature of 350 K has a volume of 4.00 L. The pressure remains constant.
What is the volume of the gas at a temperature of 175 K?
A) 8.00 L
B) 6.50 L
C) 3.75 L
D) 2.00 L
58) Charles’s Law relates the volume and temperature of a gas sample at constant pressure. What would
be the temperature of a gas sample when its volume is 0 L?
A) 273°C
B) -273°C
C) 0°C
D) 273 K
59) The pressure of a gas will increase when
A) the volume decreases.
B) the volume increases.
C) the temperature decreases.
D) the size of the container increases.
60) At a given temperature and pressure, the volume of a gas is directly proportional to the amount of gas
present. This is a statement of
A) Avogadro’s Law.
B) Boyle’s Law.
C) Charles’s Law.
D) the Ideal Gas Law.
61) In the ideal gas law equation, PV = nRT, R is known as
A) the pressure.
B) a radian.
C) the universal gas constant.
D) a revolution.
62) Use the ideal gas law to calculate the volume occupied by 0.400 mol of nitrogen gas at 3.00 atm
pressure and at 27°C. R = 0.0821 L * atm/(K*mol).
A) 3.28 L
B) 17.7 L
C) 0.296 L
D) 16.7 L
63) Use the ideal gas law to calculate the temperature when 0.300 mol of nitrogen gas at 1.40 atm pressure
occupies a volume of 11.2 L. R = 0.0821 L* atm/(K*mol).
A) 490 K
B) 637 K
C) 780 K
D) 157 K
64) Assume that you have a sample of a gas. You know the volume, the temperature and the number of
moles of the sample. Which of the following laws would you use if you wanted to calculate the pressure
of the sample?
A) Boyle’s Law
B) Charles’s Law
C) Law of Combining Volumes
D) Ideal Gas Law
6.2 True/False Questions
1) Supercritical fluids require the use of special equipment to control the temperatures and high pressures
needed for their use.
2) Most organic solvents are toxic, but supercritical fluids are generally regarded as safe.
3) Supercritical water and scCO2 are “generally regarded as safe” by the U.S. Food and Drug
Administration and are often used in the food industry.
4) Carbon dioxide is an example of a supercritical fluid.
5) It requires more energy to melt one mole of an ionic compound than one mole of a molecular
compound.
6) A covalent bond is weaker than a hydrogen bond.
7) A solution is a heterogeneous mixture.
8) The phrase “like dissolves like” means that a polar substance will dissolve readily in a polar solvent.
9) According to the kinetic-molecular theory, there is very little attraction between particles of a gas.
10) The conditions for standard temperature and pressure (STP) are 1 atm pressure and 0°C.
11) Temperatures must be converted to the Celsius temperature scale when Charles’s Law is used.
12) If the pressure of a gas rises, the gas molecules will strike the walls of its container more frequently.
(Assume that the container has a definite shape and volume.)
13) If the temperature of a gas is lowered, the gas molecules will strike the walls of its container more
frequently. (Assume that the container has a definite shape and volume.)
14) The ideal gas law can be used to determine a new volume for a gas when its temperature is changed.
6.3 Short Answer Questions
1) Melting is the change from the ________ state to the ________ state.
6.4 Essay Questions
1) Why are the melting points of ionic compounds higher than the melting points of molecular
compounds?