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Gas laws
Gas Laws Study Guide

Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.

____    1.    According to the kinetic-molecular theory, particles of matter
a. are in constant motion. c. have different colors.
b. have different shapes. d. are always fluid.



____    2.    According to the kinetic-molecular theory, gases condense into liquids because of
a. gravity. c. forces between molecules.
b. atmospheric pressure. d. elastic collisions.



____    3.    The kinetic-molecular theory explains the behavior of
a. gases only. c. liquids and gases.
b. solids and liquids. d. solids, liquids, and gases.



____    4.    Which process can be explained by the kinetic-molecular theory?
a. combustion c. condensation
b. oxidation d. replacement reactions



____    5.    According to the kinetic-molecular theory, which substances are made of particles?
a. ideal gases only c. all matter
b. all gases d. all matter except solids



____    6.    The kinetic-molecular theory explains the properties of solids, liquids, and gases in terms of the energy of the particles and
a. gravitational forces. c. diffusion.
b. the forces that act between the particles. d. the mass of the particles.



____    7.    According to the kinetic-molecular theory, particles of matter are in motion in
a. gases only. c. solids, liquids, and gases.
b. gases and liquids. d. solids only.



____    8.    An ideal gas is an imaginary gas
a. not made of particles.
b. that conforms to all of the assumptions of the kinetic theory.
c. whose particles have zero mass.
d. made of motionless particles.



____    9.    Unlike in an ideal gas, in a real gas
a. all particles move in the same direction.
b. all particles have the same kinetic energy.
c. the particles cannot diffuse.
d. the particles exert attractive forces on each other.



____    10.    A real gas
a. does not obey all the assumptions of the kinetic-molecular theory.
b. consists of particles that do not occupy space.
c. cannot be condensed.
d. cannot be produced in scientific laboratories.



____    11.    If two moving steel balls collide, their total energy after the collision is the same as before. This is an example of
a. Boyle's law. c. an elastic collision.
b. the law of gravity. d. both Boyle's law and Charles's law.



____    12.    Which is NOT an assumption of the kinetic-molecular theory?
a. Matter is composed of tiny particles.
b. The particles of matter are in continual motion.
c. The total kinetic energy of colliding particles remains constant.
d. When individual particles collide, energy is transferred.



____    13.    According to the kinetic-molecular theory, what is the most significant difference between gases and liquids?
a. the shapes of the particles
b. the mass of each particle
c. the distance between the particles
d. the type of collision that occurs between particles



____    14.    According to the kinetic-molecular theory, particles of a gas
a. attract each other but do not collide.
b. repel each other and collide.
c. neither attract nor repel each other but collide.
d. neither attract nor repel each other and do not collide.



____    15.    Which is an example of gas diffusion?
a. inflating a flat tire
b. the odor of perfume spreading throughout a room
c. a cylinder of oxygen stored under high pressure
d. All of the above



____    16.    By which process do gases take the shape of their container?
a. evaporation c. adhesion
b. expansion d. diffusion



____    17.    If a gas with an odor is released in a room, it quickly can be detected across the room because it
a. diffuses. c. is compressed.
b. is dense. d. condenses.



____    18.    Which substance has the lowest density?
a. H2O(g) c. Hg(l)
b. H2O(l) d. Hg(g)



____    19.    The density of a substance undergoes the greatest change when the substance changes from a
a. liquid to a gas. c. solid to a liquid.
b. liquid to a solid. d. a molecular solid to an ionic solid.



____    20.    According to the kinetic-molecular theory, how does a gas expand?
a. Its particles become larger.
b. Collisions between particles become elastic.
c. Its temperature rises.
d. Its particles move greater distances.



____    21.    Diffusion between two gases occurs most rapidly if the gases are at a
a. high temperature and the molecules are small.
b. low temperature and the molecules are large.
c. low temperature and the molecules are small.
d. high temperature and the molecules are large.



____    22.    Which is an example of effusion?
a. air slowly escaping from a pinhole in a tire
b. the aroma of a cooling pie spreading across a room
c. helium dispersing into a room after a balloon pops
d. oxygen and gasoline fumes mixing in an automobile carburetor



____    23.    What happens to the volume of a gas during compression?
a. The volume increases.
b. The volume decreases.
c. The volume remains constant.
d. It is impossible to tell because all gases are different.



____    24.    Under which conditions do real gases most resemble ideal gases?
a. low pressure and low temperature c. high pressure and high temperature
b. low pressure and high temperature d. high pressure and low temperature



____    25.    When does a real gas behave like an ideal gas?
a. when the particles are far apart
b. when the kinetic energy of the particles is low
c. when the pressure is high
d. when the gas is liquefied



____    26.    Why doesn't a gas at a low temperature behave like an ideal gas?
a. There is too much space between the particles.
b. The attractive forces are too weak.
c. The kinetic energy of the particles is too low.
d. The particles undergo chemical reactions.



____    27.    Which gases behave most like an ideal gas?
a. gases composed of highly polar molecules
b. gases composed of monatomic, nonpolar molecules
c. gases composed of diatomic, polar molecules
d. gases near their condensation temperatures



____    28.    As a real gas deviates from ideal gas behavior, the particles
a. move farther apart. c. collide more energetically.
b. gain kinetic energy. d. experience stronger attractive forces.



____    29.    The behavior of a gas under very high pressure is likely to
a. conform to the assumptions of the kinetic-molecular theory.
b. deviate from ideal gas behavior.
c. show ideal gas behavior.
d. be nonpolar.



____    30.    Pressure is the force per unit
a. volume. c. length.
b. surface area. d. depth.



____    31.    What is the SI unit of force?
a. torr c. pound
b. pascal d. newton



____    32.    If force is held constant as surface area decreases, pressure
a. remains constant.
b. decreases.
c. increases.
d. increases or decreases, depending on the volume change.



____    33.    What does the constant bombardment of gas molecules against the inside walls of a container produce?
a. temperature c. pressure
b. density d. diffusion



____    34.    What is the definition of pressure?
a.

b.
c. pressure = force ´ area
d.



____    35.    Why does a can collapse when a vacuum pump removes air from the can?
a. The inside and outside forces balance out and crush the can.
b. The unbalanced outside force from atmospheric pressure crushes the can.
c. The atmosphere exerts pressure on the inside of the can and crushes it.
d. The vacuum pump creates a force that crushes the can.



____    36.    What instrument measures atmospheric pressure?
a. barometer c. vacuum pump
b. manometer d. torrometer



____    37.    What instrument measures the pressure of an enclosed gas?
a. barometer c. vacuum pump
b. manometer d. torrometer



____    38.    A pressure of 745 mm Hg equals
a. 745 torr. c. 1 pascal.
b. 1 torr. d. 745 pascal.



____    39.    Convert the pressure 0.75 atm to mm Hg.
a. 101.325 mm Hg c. 570 mm Hg
b. 430 mm Hg d. 760 mm Hg



____    40.    Convert the pressure 0.840 atm to mm Hg.
a. 365 mm Hg c. 638 mm Hg
b. 437 mm Hg d. 780 mm Hg



____    41.    Convert the pressure 0.600 atm to mm Hg.
a. 325 mm Hg c. 572 mm Hg
b. 456 mm Hg d. 708 mm Hg



____    42.    Convert the pressure 2.50 atm to kPa.
a. 1 kPa c. 760 kPa
b. 253 kPa d. 1000 kPa



____    43.    Convert the pressure 1.30 atm to kPa.
a. 2 kPa c. 132 kPa
b. 115 kPa d. 245 kPa



____    44.    Standard temperature is exactly
a. 100ºC. c. 0ºC.
b. 273ºC. d. 0 K.



____    45.    Standard pressure is the pressure exerted by a column of mercury exactly
a. 273 mm high. c. 760 cm high.
b. 760 mm high. d. 1.00 m high.



____    46.    Standard pressure is exactly
a. 1 atm. c. 101.325 atm.
b. 760 atm. d. 101 atm.



____    47.    If the height of mercury in a barometer at 0ºC is less than 760 mm Hg, then
a. the atmospheric pressure is less than standard atmospheric pressure.
b. the atmospheric pressure is greater than standard atmospheric pressure.
c. the atmospheric pressure is equal to standard atmospheric pressure.
d. the atmospheric pressure cannot be determined.



____    48.    If the pressure and temperature of a gas are held constant and some gas is added to the container or some is allowed to escape, a change in which of the following can be observed?
a. kinetic energy c. elasticity
b. volume d. fluidity



____    49.    If the temperature of a fixed quantity and volume of gas changes, what also changes?
a. pressure c. mass
b. density d. formula



____    50.    To observe the effects of changing pressure on the volume of a gas, factors that must be kept constant are the gas's temperature and
a. density. c. elasticity.
b. quantity. d. All of the above



____    51.    To study the relationship between the temperature and volume of a gas, which factor must be held constant?
a. elasticity c. kinetic energy
b. fluidity d. pressure



____    52.    If the temperature of a fixed quantity of gas decreases and the pressure remains unchanged,
a. its volume increases. c. its volume decreases.
b. its volume is unchanged. d. its density decreases.



____    53.    Suppose the temperature of the air in a balloon is increased. If the pressure remains constant, what quantity must change?
a. volume c. compressibility
b. number of molecules d. adhesion



____    54.    Two gases have the same temperature but different pressures. The kinetic-molecular theory does NOT predict that
a. molecules in both gases have the same average kinetic energies.
b. molecules in the low-pressure gas travel farther before they collide with other molecules.
c. both gases have the same densities.
d. all collisions of the molecules are elastic.



____    55.    Why does the air pressure inside the tires of a car increase when the car is driven?
a. Some of the air has leaked out.
b. The air particles collide with the tire after the car is in motion.
c. The air particles inside the tire increase their speed because their temperature rises.
d. The atmosphere compresses the tire.



____    56.    If the temperature of a container of gas remains constant, how could the pressure of the gas increase?
a. The mass of the gas molecules increases.
b. The diffusion of the gas molecules increases.
c. The size of the container increases.
d. The number of gas molecules in the container increases.



____    57.    The gas pressure inside a container decreases when
a. the number of gas molecules is increased.
b. the number of gas molecules is decreased.
c. the temperature is increased.
d. the number of molecules is increased and the temperature is increased.



____    58.    If the temperature remains constant, V and P represent the original volume and pressure, and V' and P' represent the new volume and pressure, what is the mathematical expression for Boyle's law?
a. P'V = V'P c. V'P' = VP
b. VV' = PP' d.



____    59.    Pressure and volume changes at a constant temperature can be calculated using
a. Boyle's law. c. Kelvin's law.
b. Charles's law. d. Dalton's law.



____    60.    The volume of a gas is 400.0 mL when the pressure is 1.00 atm. At the same temperature, what is the pressure at which the volume of the gas is 2.0 L?
a. 0.5 atm c. 0.20 atm
b. 5.0 atm d. 800 atm



____    61.    The pressure of a sample of helium is 2.0 atm in a 200-mL container. If the container is compressed to 10 mL without changing the temperature, what is the new pressure?
a. 200 atm c. 100 atm
b. 0.10 atm d. 40. atm



____    62.    A sample of oxygen occupies 560. mL when the pressure is 800.00 mm Hg. At constant temperature, what volume does the gas occupy when the pressure decreases to 700.0 mm Hg?
a. 80.0 mL c. 600. mL
b. 490. mL d. 640. mL



____    63.    A sample of argon gas at standard pressure occupies 1000. mL. At constant temperature, what volume does the gas occupy if the pressure increases to 800. mm Hg?
a. 500. mL c. 950. mL
b. 760. mL d. 1053. mL



____    64.    A sample of gas collected at 750. mm Hg occupies 250. mL. At constant temperature, what pressure does the gas exert if the volume increases to 300. mL?
a. 50. mm Hg c. 625. mm Hg
b. 550. mm Hg d. 900. mm Hg



____    65.    At 710. mm Hg, a sample of nitrogen gas occupies 625 mL. What volume does the gas occupy if the temperature remains constant and the pressure increases to 760. mm Hg?
a. 135 mL c. 600 mL
b. 584 mL d. 669 mL



____    66.    A 425 mL sample of gas is collected at 780. mm Hg. If the temperature remains constant and the pressure falls to 680. mm Hg, what is the new volume?
a. 325 mL c. 488 mL
b. 370 mL d. 525 mL



____    67.    If V is the original volume, V' is the new volume, T is the original Kelvin temperature, and T' is the new Kelvin temperature, how is Charles's law expressed mathematically?
a.

c.

b. d.



____    68.    The volume of a gas is 5.0 L when the temperature is 5.0ºC. If the temperature is increased to 10.0ºC without changing the pressure, what is the new volume?
a. 2.5 L c. 5.1 L
b. 4.8 L d. 10.0 L



____    69.    At 7.0ºC, the volume of a gas is 49 mL. At the same pressure, its volume is 74 mL at what temperature?
a. 3.0ºC c. 120ºC
b. 16ºC d. 150ºC



____    70.    A 180.0 mL volume of gas is measured at 87.0ºC. If the pressure remains unchanged, what is the volume of the gas at standard temperature?
a. 0.0 mL c. 136 mL
b. 0.5 mL d. 410 mL



____    71.    The volume of a gas is 93 mL when the temperature is 91ºC. If the temperature is reduced to 0ºC without changing the pressure, what is the new volume of the gas?
a. 70 mL c. 120 mL
b. 100 mL d. 273 mL



____    72.    The volume of a gas is 400. mL at 30.0ºC. If the temperature is increased to 50.0ºC without changing the pressure, what is the new volume of the gas?
a. 375 mL c. 426 mL
b. 400 mL d. 600 mL



____    73.    If a gas occupies 950.0 mL at standard temperature, what volume does it occupy at 25.00ºC if the pressure remains constant?
a. 870.0 mL c. 1000.0 mL
b. 966.0 mL d. 1037 mL



____    74.    If the temperature of 50.0 L of a gas at 40.0ºC falls by 10.0Cº, what is the new volume of the gas if the pressure is constant?
a. 45.0 L c. 52.0 L
b. 48.4 L d. 55.0 L



____    75.    Why would the pressure of a sample of gas at a constant volume fall 75 mm Hg?
a. The container exploded. c. The temperature decreased.
b. The temperature increased. d. Fewer particles were present.



____    76.    On a cold winter morning when the temperature is –13ºC, the air pressure in an automobile tire is 1.5 atm. If the volume does not change, what is the pressure after the tire has warmed to 15ºC?
a. –1.5 atm c. 3.0 atm
b. 1.7 atm d. 19.5 atm



____    77.    The pressure of a sample of gas of constant volume is 2.0 atm at 30.ºC. What is the pressure of this sample at 20.ºC?
a. 1.0 atm c. 2.1 atm
b. 1.9 atm d. 20 atm



____    78.    The pressure of a 1000. mL sample of gas at 10.0ºC increases from 700. mm Hg to 900. mm Hg. If the volume is unchanged, what is the new temperature?
a. 0ºC c. 30ºC
b. 24ºC d. 91ºC



____    79.    The pressure of a sample of gas at a constant volume is 8.0 atm at 70.ºC. What is the pressure at 20.ºC?
a. 0.16 atm c. 9.4 atm
b. 6.8 atm d. 58 atm



____    80.    The temperature of a sample of gas at 4.0 atm and 15.ºC increases to 30.ºC. If the volume is unchanged, what is the new gas pressure?
a. 3.8 atm c. 8 atm
b. 4.2 atm d. 19 atm



____    81.    The pressure of a sample of gas increases from 450. mm Hg to 500. mm Hg. If the volume is constant and the temperature of the gas was 0.0ºC, what is the new gas temperature?
a. –30.ºC c. 50.ºC
b. 30.ºC d. 273ºC



____    82.    As the temperature of a sample of gas falls from 45.0ºC to 30.0ºC, its pressure falls to 300. mm Hg. If the volume did not change, what was the original gas pressure?
a. 285 mm Hg c. 400. mm Hg
b. 315 mm Hg d. 615 mm Hg



____    83.    A sample of gas at 6.0 atm and 5.0ºC increases in temperature to 35ºC. If the volume is unchanged, what is the new pressure?
a. 5.4 atm c. 36 atm
b. 6.6 atm d. 42 atm



____    84.    If V, P, and T represent the original volume, pressure, and temperature in the correct units, and V', P', and T' represent the new conditions, what is the combined gas law?
a.

c.
b. d.



____    85.    The volume of a sample of oxygen is 300.0 mL when the pressure is 1 atm and the temperature is 27.0ºC. At what temperature is the volume 1.00 L and the pressure 0.500 atm?
a. 22.0ºC c. 0.50 K
b. 45.0ºC d. 227ºC



____    86.    Suppose that the pressure of 1.00 L of gas is 380. mm Hg when the temperature is 200. K. At what temperature is the volume 2.00 L and the pressure 0.750 atm?
a. 1.00 K c. 219ºC
b. 600. K d. 67.0 K



____    87.    The volume of a gas collected when the temperature is 11.0ºC and the pressure is 710 mm Hg measures 14.8 mL. What is the calculated volume of the gas at 20.0ºC and 740 mm Hg?
a. 7.8 mL c. 14.6 mL
b. 13.7 mL d. 15 mL



____    88.    The volume of a sample of hydrogen is 798 mL and it exerts 621 mm Hg pressure at 5.00ºC. What volume does it occupy at standard temperature and pressure?
a. 520. mL c. 745 mL
b. 640. mL d. 960 mL



____    89.    A 30.-L sample of gas exerts 200. mm Hg pressure at 10ºC. What volume does the gas have at 300. mm Hg and 25ºC?
a. 9.0 L c. 21 L
b. 17 L d. 42 L



____    90.    At 0.500 atm and 15.0ºC a sample of gas occupies 120. L. What volume does it occupy at 0.250 atm and 10.0ºC?
a. 60 L c. 236 L
b. 111 L d. 480 L



____    91.    A 70.0 L sample of gas at 20.0ºC and 600. mm Hg expands to 90.0 L at 15.0ºC. What is the new gas pressure?
a. 318 mm Hg c. 583 mm Hg
b. 459 mm Hg d. 710 mm Hg



____    92.    A 75.0 mL sample of gas exerts 200. mm Hg pressure at 30ºC. What pressure does it exert at 35.0ºC if the volume expands to 80.0 mL?
a. 90.0 mm Hg c. 190 mm Hg
b. 161 mm Hg d. 219 mm Hg



____    93.    A 150.0 L sample of gas is collected at 1.20 atm and 25ºC. What volume does the gas have at 1.50 atm and 20.0ºC?
a. 94 L c. 143 L
b. 120 L d. 183 L



____    94.    Who developed the concept that the total pressure of a mixture of gases is the sum of their  partial pressures?
a. Charles c. Kelvin
b. Boyle d. Dalton



____    95.    To correct for the partial pressure of water vapor, the vapor pressure of H2O at the collecting temperature is
a. divided by 22.4. c. subtracted from the total gas pressure.
b. multiplied by 22.4. d. added to the total gas pressure.



____    96.    Three samples of gas each exert 740. mm Hg in separate 2 L containers. What pressure do they exert if they are all placed in a single 2 L container?
a. 247 mm Hg c. 1480 mm Hg
b. 740 mm Hg d. 2220 mm Hg



____    97.    A mixture of four gases exerts a total pressure of 860 mm Hg. Gases A and B each exert 220 mm Hg. Gas C exerts 110 mm Hg. What pressure is exerted by gas D?
a. 165 mm Hg c. 860 mm Hg
b. 310 mm Hg d. cannot be determined



____    98.    If five gases in a cylinder each exert 1 atm, what is the total pressure exerted by the gases?
a. 0.2 atm c. 1 atm
b. 0.5 atm d. 5 atm



       Water Vapor Pressure
Temperature (ºC) Pressure (mm Hg)
0
    4.6
5
    6.5
10
    9.2
15
    12.8
20
    17.5
25
    23.8
30
    31.8
35
    42.2
40
    55.3
50
    92.5



____    99.    What is the partial pressure of water vapor in oxygen gas collected by water displacement at 10ºC and 750 mm Hg?
a. 9.2 mm Hg c. 750 mm Hg
b. 740.8 mm Hg d. 759.2 mm Hg



____    100.    A sample of gas is collected by water displacement at 600.0 mm Hg and 30ºC. What is the partial pressure of the gas?
a. 568.2 mm Hg c. 630 mm Hg
b. 600.0 mm Hg d. 631.8 mm Hg



____    101.    A sample of nitrogen is collected by water displacement at 730.0 mm Hg and 20ºC. What is the partial pressure of the nitrogen?
a. 17.5 mm Hg c. 717.2 mm Hg
b. 712.5 mm Hg d. 747.5 mm Hg



____    102.    Gay-Lussac recognized that at constant temperature and pressure, the volumes of gaseous reactants and products
a. always equal 1 L.
b. add up to 22.4 L.
c. equal R.
d. can be expressed as ratios of small whole numbers.



____    103.    When Gay-Lussac's law of combining volumes holds, which of the following can be expressed in ratios of small whole numbers?
a. pressure before and pressure after reaction
b. volumes of gaseous reactants and products
c. Kelvin temperatures
d. molar masses of products and reactants



____    104.    The law of combining volumes applies only to gas volumes
a. measured at constant temperature and pressure.
b. that equal 1 L.
c. that equal 22.4 L.
d. measured at STP.



____    105.    The reaction of two volumes of hydrogen gas with one volume of oxygen gas to produce two volumes of water vapor is an example of
a. the ideal gas law.
b. Graham's law of effusion.
c. Gay-Lussac's law of combining volumes of gases.
d. Avogadro's law.



____    106.    In the equation H2(g) + Cl2(g) ® 2HCl(g), one volume of hydrogen yields how many volumes of hydrogen chloride?
a. 1 c. 3
b. 2 d. 4



____    107.    If 0.5 L of O2(g) reacts with H2 to produce 1 L of H2O(g), what is the volume of H2O(g) obtained from 1 L of O2(g)?
a. 0.5 L c. 2 L
b. 1.5 L d. Cannot be determined



____    108.    In the equation C + O2(g) ® CO2(g), one volume of O2 yields how many volumes of CO2?
a. 1 c. 3
b. 2 d. 4



____    109.    The principle that under similar pressures and temperatures, equal volumes of gases contain the same number of molecules is attributed to
a. Berthollet. c. Avogadro.
b. Proust. d. Dalton.



____    110.    Equal volumes of diatomic gases under the same conditions of temperature and pressure contain the same number of
a. protons. c. molecules.
b. ions. d. Dalton's "ultimate particles."



____    111.    If gas A has a molar mass greater than that of gas B and samples of each gas at identical temperatures and pressures contain equal numbers of molecules, then
a. the volumes of gas A and gas B are equal.
b. the volume of gas A is greater than that of gas B.
c. the volume of gas B is greater than that of gas A.
d. their volumes are proportional to their molar masses.



____    112.    At constant temperature and pressure, gas volume is directly proportional to the
a. molar mass of the gas. c. density of the gas at STP.
b. number of moles of gas. d. rate of diffusion.



____    113.    The expression V = kn is a statement of
a. the ideal gas law. c. Graham's law of effusion.
b. the law of combining volumes. d. Avogadro's principle.



____    114.    Avogadro's principle led to the realization that the molecules of some substances
a. could not react. c. were invisible.
b. were not composed of atoms. d. were made of more than one atom.



____    115.    In the expression V = kn, n represents
a. the gas constant. c. the number of moles of gas.
b. Avogadro's number. d. a constant.



____    116.    According to Avogadro's law, 1 L of H2(g) and 1 L of O2(g) at the same temperature and pressure
a. have the same mass. c. contain 1 mol of gas each.
b. have unequal volumes. d. contain equal numbers of molecules.



____    117.    The standard molar volume of a gas is all of the following except
a. the volume occupied by 1 mol of a gas at STP.
b. equal for all gases under the same conditions.
c. 22.4 L at STP.
d. dependent upon the size of the molecules.



____    118.    The standard molar volume of a gas at STP is
a. 22.4 L. c. g-mol wt/22.4 L.
b. g/22.4 L. d. 1 L.



____    119.    The standard molar volume of a gas at STP is all of the following except
a. the volume occupied by 1 mol of the gas.
b. 22.4 g.
c. 22.4 L.
d. the volume occupied by one molar mass of the gas.



____    120.    What is the volume occupied by 1 mol of oxygen at STP?
a. 11.2 L c. 22.4 L
b. 16.0 L d. 32.0 L



____    121.    What is the volume occupied by 1 mol of water vapor at STP?
a. 11.2 L c. 22.4 L
b. 18.0 L d. 33.6 L



____    122.    At STP, the standard molar volume of a gas of known volume can be used to calculate the
a. number of moles of gas. c. gram-molecular weight.
b. rate of diffusion. d. gram-molecular volume.



____    123.    If the molecular formula of a gas is known, the molar volume is used directly in solving
a. mass-mass problems. c. percentage composition problems.
b. the volume of any mass of gas. d. gas volume–gas volume problems.



____    124.    Knowing the mass and volume of a gas at STP allows one to calculate the
a. identity of the gas. c. condensation point of the gas.
b. molar mass of the gas. d. rate of diffusion of the gas.



____    125.    What is the molar mass of gas at STP?
a. density of the gas multiplied by the mass of 1 mol
b. density of the gas divided by the mass of 1 mol
c. density of the gas multiplied by 22.4 L
d. density of the gas divided by 22.4 L



____    126.    A 1.00 L sample of a gas has a mass of 1.92 g at STP. What is the molar mass of the gas?
a. 1.92 g/mol c. 22.4 g/mol
b. 19.2 g/mol d. 43.0 g/mol



____    127.    A 1.00 L sample of a gas has a mass of 0.716 g at STP. What is the molar mass of the gas?
a. 0.716 g/mol c. 7.16 g/mol
b. 1.60 g/mol d. 16.0 g/mol



____    128.    A 1.00 L sample of a gas has a mass of 1.25 g at STP. What is the mass of 1 mol of this gas?
a. a little less then 1.0 g c. 22.4 g
b. 1.25 g d. 28.0 g



____    129.    A 1.00 L sample of a gas has a mass of 1.7 g at STP. What is the molar mass of the gas?
a. 0.076 g/mol c. 38 g/mol
b. 13.2 g/mol d. 170 g/mol



____    130.    The ideal gas law is equivalent to Charles's law when
a. the number of moles and the pressure are constant.
b. the number of moles and the temperature are constant.
c. the volume equals 22.4 L.
d. R equals zero.



____    131.    The ideal gas law is equivalent to Boyle's law when
a. Avogadro's number is reached.
b. R equals zero.
c. the pressure is 1 atm.
d. the number of moles and the temperature are constant.



____    132.    The ideal gas law is equivalent to Avogadro's law when
a. the volume is 22.4 L.
b. 1 mol of a gas is present.
c. the pressure and the temperature are constant.
d. the volume and pressure are constant.



____    133.    The ideal gas law combines Boyle's law, Charles's law, and
a. Graham's law. c. Raoult's law.
b. Avogadro's law. d. Dalton's principle.



____    134.    All of the following equations are statements of the ideal gas law except
a. P = nRTV c.
b. d.



____    135.    When pressure, volume, and temperature are known, the ideal gas law can be used to calculate
a. the chemical formula. c. molar amount.
b. the ideal gas constant. d. compressibility.



____    136.    Which is a common unit for the ideal gas constant R?
a. L·atm c.

b. mol·K d.



____    137.    What is the value of the gas constant?
a. 0.0821 c. 0.0281

b. 0.0281 L·atm d. 0.0821 mol·K



____    138.    The value of R, the ideal gas constant, can be calculated from measured values of a gas's pressure, volume, temperature, and
a. molar amount. c. rate of diffusion.
b. chemical formula. d. density.



____    139.    In the ideal gas law, what is the value that must be calculated from other measurements?
a. P c. T
b. V d. R



____    140.    The gas constant, R, has the value of
a. 0.0821 c. 0.0821
b. 0.0821 d. 0.0821



____    141.    Calculate the approximate volume of a 0.600 mol sample of gas at 15.0ºC and a pressure of 1.10 atm.
a. 12.9 L c. 24.6 L
b. 22.4 L d. 129 L



____    142.    Calculate the approximate temperature of a 0.50 mol sample of gas at 750 mm Hg and a volume of 12 L.
a. –7ºC c. 15ºC
b. 11ºC d. 288ºC



____    143.    What is the pressure exerted by 1.2 mol of a gas with a temperature of 20.ºC and a volume of 9.5 L?
a. 0.030 atm c. 3.0 atm
b. 1.0 atm d. 30. atm



____    144.    A sample of gas at 25ºC has a volume of 11 L and exerts a pressure of 660 mm Hg. How many moles of gas are in the sample?
a. 0.39 mol c. 9.3 mol
b. 3.9 mol d. 87 mol



____    145.    What is the approximate volume of gas in a 1.50 mol sample that exerts a pressure of 0.922 atm and has a temperature of 10.0ºC?
a. 13 L c. 37.8 L
b. 14.2 L d. 378 L



____    146.    What pressure is exerted by 0.750 mol of a gas at a temperature of 0.00ºC and a volume of 5.00 L?
a. 2.1 atm c. 4.98 atm
b. 3.4 atm d. 760. atm



____    147.    A gas sample with a mass of 0.467 g is collected at 20.ºC and 732.5 mm Hg. The volume is 200. mL. What is the molar mass of the gas?
a. 58 g/mol c. 290 g/mol
b. 180 g/mol d. 730 g/mol



____    148.    A gas sample with a mass of 0.686 g is collected at 20.ºC and 722.5 mm Hg. The volume is 350. mL. What is the molar mass of the gas?
a. 0.31 g/mol c. 50. g/mol
b. 2.2 g/mol d. 720 g/mol



____    149.    A gas sample with a mass of 2.50 g is collected at 20.0ºC and 732.5 mm Hg. The volume is 1.28 L. What is the molar mass of the gas?
a. 1.26 g/mol c. 13.7 g/mol
b. 2.04 g/mol d. 48.8 g/mol



____    150.    A gas sample with a mass of 0.934 g is collected at 20.0ºC and 733.5 mm Hg. The volume is 200.0 mL. What is the molar mass of the gas?
a. 116 g/mol c. 586 g/mol
b. 358 g/mol d. 1464.0 g/mol



____    151.    A gas sample with a mass of 5.16 g is collected at 28ºC and 740 mm Hg. The volume is 1.00 L. What is the molar mass of the gas?
a. 0.395 g/mol c. 130 g/mol
b. 0.97 g/mol d. 300 g/mol



____    152.    A gas sample with a mass of 0.250 g is collected at 150.0ºC and 720. mm Hg. The volume is 85.0 mL. What is the molar mass of the gas?
a. 0.0023 g/mol c. 108 g/mol
b. 1.76 g/mol d. 238.0 g/mol



____    153.    A gas sample with a mass of 12.8 g exerts a pressure of 1.2 atm at 15ºC and a volume of 3.94 L. What is the molar mass of the gas?
a. 19 g/mol c. 64 g/mol
b. 32 g/mol d. 128 g/mol



____    154.    If n and T are constant, the ideal gas law reduces to
a. Charles's law. c. Avogadro's law.
b. Boyle's law. d. zero.



____    155.    If n and P are constant, the ideal gas law reduces to
a. Charles's law. c. Avogadro's law.
b. Boyle's law. d. zero.



____    156.    If P and T are constant, the ideal gas law reduces to
a. Charles's law. c. Avogadro's law.
b. Boyle's law. d. zero.



____    157.    When the ideal gas law reduces to PV = k, the expression is equivalent to
a. Avogadro's law. c. Charles's law.
b. Avogadro's number. d. Boyle's law.



____    158.    When the ideal gas law reduces to V = kT, the expression is equivalent to
a. Boyle's law. c. Avogadro's principle.
b. Charles's law. d. Gay-Lussac's law.



____    159.    When the ideal gas law reduces to V = kn, the expression is equivalent to
a. Avogadro's law. c. Charles's law.
b. Avogadro's number. d. Boyle's law.



____    160.    For reactants or products that are gases, the coefficients in the chemical equation indicate
a. the number of grams of each substance. c. molar volume.
b. volume. d. density.



____    161.    If the volume of the gaseous reactants and products in the equation 2C2H6 + 7O2 ® 4CO2 + 6H2O are measured at 1 atm and 25ºC, the substance that could not be included in the volume relationship has what formula?
a. C2H6 c. CO2
b. O2 d. H2O



____    162.    In a chemical equation, the coefficients for reactants and products that are gases indicate
a. volumes at STP. c. molar mass of each substance.
b. volume ratios. d. densities.



____    163.    What law helps explain the volume ratios in a chemical reaction?
a. Charles's law c. Boyle's law
b. Graham's law d. Gay-Lussac's law of combining volumes



____    164.    Volumes of gaseous reactants and products in a chemical reaction can be expressed as ratios of small whole numbers
a. if all reactants and products are gases.
b. if standard temperature and pressure are maintained.
c. if constant temperature and pressure are maintained.
d. if each mass equals 1 mol.



____    165.    According to Avogadro's law, in a chemical equation equal volumes of gases contain equal
a. numbers of molecules. c. temperatures.
b. pressures. d. masses.



____    166.    The ratios of the volumes of the gaseous reactants and products in a chemical reaction at constant temperature and pressure can be determined from the
a. formulas. c. subscripts in the balanced equation.
b. coefficients in the balanced equation. d. gas constant.



____    167.    In the reaction 2C + O2(g) ® 2CO(g), what is the volume ratio of O2 to CO?
a. 1:1 c. 1:2
b. 2:1 d. 2:2



____    168.    In the reaction 2H2(g) + O2(g) ® 2H2O(g), what is the volume ratio of H2 to H2O?
a. 1:1 c. 4:3
b. 2:3 d. 4:6



____    169.    In the reaction N2(g) + 2O2(g) ® 2NO2(g), what is the volume ratio of N2 to NO2?
a. 1:1 c. 2:1
b. 1:2 d. 2:5



____    170.    In the reaction 2H2(g) + O2(g) ® 2H2O(g), what is the volume ratio of O2 to H2O?
a. 1:1 c. 1:2
b. 2:1 d. 2:2



____    171.    In the reaction H2(g) + Cl2(g) ® 2HCl, what is the volume ratio of Cl2 to HCl?
a. 1:1 c. 2:1
b. 1:2 d. 2:2



____    172.    In the reaction H2(g) + Cl2(g) ® 2HCl, what is the volume ratio of H2 to HCl?
a. 1:1 c. 2:1
b. 1:2 d. 2:2



____    173.    In the reaction H2(g) + Cl2(g) ® 2HCl, what is the volume ratio of H2 to Cl2?
a. 1:1 c. 2:1
b. 1:2 d. 3:2



____    174.    The equation for the production of methane is C + 2H2(g) ® CH4(g). How many liters of hydrogen are needed to produce 20 L of methane?
a. 2.0 L c. 22.4 L
b. 20 L d. 40 L



____    175.    The equation for the complete combustion of methane is CH4(g) + 2O2(g) ® 2H2O(g) + CO2(g). If 50 L of methane at STP are burned, what volume of carbon dioxide will be produced at STP?
a. 16.6 L c. 50 L
b. 25 L d. 100 L



____    176.    When hydrogen burns, water vapor is produced. The equation is 2H2(g) + O2(g) ® 2H2O(g). If 12 L of oxygen are consumed, what volume of water vapor is produced?
a. 1 L c. 12 L
b. 2 L d. 24 L



____    177.    For the complete combustion of 100. L of CO, the volume of oxygen required is
a. 23.8 L c. 238 L
b. 50.0 L d. 500. L



____    178.    What is the number of moles of H2 produced when 23 g of sodium react with water according to the equation 2Na(s) + 2H2O(l) ® 2NaOH(aq) + H2(g)?
a. 0.50 mol c. 2 mol
b. 1 mol d. 4 mol



____    179.    Chlorine is produced by the reaction 2HCl(g) ® H2(g) + Cl2(g). How many grams of HCl (36.5 g/mol) must be used to produce 10 L of chlorine at STP?
a. 15.8 g c. 32.6 g
b. 30.2 g d. 36.5 g



____    180.    Iron oxide, FeO2, is produced by the reaction Fe + O2 ® FeO2 (87.8 g/mol). How many grams of FeO2 can be produced from 50 L of O2 at STP?
a. 19.5 g c. 50 g
b. 37.8 g d. 196. g



____    181.    When carbon burns, carbon dioxide is produced by the reaction C + O2 ® CO2. If 14 L of CO2 are produced at STP, how many grams of carbon (atomic mass 12) were used?
a. 7.5 g c. 17.5 g
b. 11.2 g d. 75 g



____    182.    What is the process by which molecules of a gas randomly encounter and pass through a small opening in a container?
a. diffusion c. distillation
b. osmosis d. effusion



____    183.    According to Graham's law, the rates of diffusion of two gases at the same temperature and pressure are inversely proportional to
a. their volumes. c. their compressibilities.
b. the square roots of their molar masses. d. their rates of effusion.



____    184.    What determines the average kinetic energy of the molecules of any gas?
a. temperature c. temperature and pressure
b. pressure d. molar mass



____    185.    The equation MAvA2 = MBvB2 is an expression of
a. Gay-Lussac's law. c. Graham's law.
b. Avogadro's law. d. Boyle's law.



____    186.    According to Graham's law, two gases at the same temperature and pressure will have different rates of diffusion because they have different
a. volumes. c. kinetic energies.
b. molar masses. d. condensation points.



____    187.    In Graham's equation, the square roots of the molar masses can be substituted with the square roots of the
a. gas densities. c. compressibilities.
b. molar volumes. d. gas constants.



____    188.    Suppose that two gases with unequal molar masses were injected into opposite ends of a long tube at the same time and allowed to diffuse toward the center. They should begin to mix
a. in approximately five minutes.
b. closer to the end that held the heavier gas.
c. closer to the end that held the lighter gas.
d. exactly in the middle.



Element Atomic mass

Argon 39.948
Bromine 79.904
Carbon 12.011
Chlorine 35.453
Fluorine 18.998
Helium 4.0026
Hydrogen 1.0079
Nitrogen 14.007
Oxygen 15.999



____    189.    How many times greater is the rate of effusion of molecular fluorine than that of molecular bromine at the same temperature and pressure?
a. 2 c. 4
b. 3 d. 7



____    190.    How many times greater is the rate of effusion of oxygen gas than that of carbon dioxide gas at the same temperature and pressure?
a. 1.2 c. 12
b. 2.1 d. They are equal.



____    191.    A sample of helium diffuses 4.57 times faster than an unknown gas diffuses. What is the molar mass of the unknown gas?
a. 12 g/mol c. 38.8 g/mol
b. 18.2 g/mol d. 83.6 g/mol



____    192.    A sample of helium diffuses 6.3 times faster than an unknown gas diffuses. What is the molar mass of the unknown gas?
a. 1.05 g/mol c. 25.2 g/mol
b. 3.8 g/mol d. 160 g/mol



____    193.    A sample of hydrogen gas diffuses 3.8 times faster than an unknown gas diffuses. What is the molar mass of the unknown gas?
a. 3.8 g/mol c. 22.4 g/mol
b. 7.6 g/mol d. 28 g/mol



Short Answer

    194.    Why are gases described as fluid?

    195.    Why must a barometer be open to the air at one end and closed at the other?

    196.    What are standard temperature and pressure? Why was a standard needed?

Problem

Element Atomic mass

Argon 39.948
Bromine 79.904
Carbon 12.011
Chlorine 35.453
Fluorine 18.998
Helium 4.0026
Hydrogen 1.0079
Nitrogen 14.007
Oxygen 15.999



    197.    Methane, CH4, and propane, C3H8, are two components of the natural gas burned in Bunsen burners. If a methane molecule travels at 675 m/s from a gas jet, how fast does the propane molecule travel?

    198.    A nitrogen molecule in the compressed air pumped into your car tires effuses at a velocity of 535 m/s. How fast does the oxygen in the compressed air effuse?

    199.    A helium balloon and a balloon filled with CO2 are punctured with holes of similar sizes. At what speed does the helium effuse if the CO2 effuses at a speed of 410. m/s?

    200.    A gas sprayed from an aerosol can effuses 2.08 times slower than nitrogen diffuses. What is the molar mass of the unknown gas?

    201.    A gas that effuses 1.19 times as slowly as does nitrogen is added to light bulbs. What is the molar mass of the unknown gas?

    202.    A steam vent releases an unknown gas along with steam. This gas travels 1.56 times as slowly as the steam. What is the molar mass of the unknown gas?

Essay

    203.    Explain how a barometer works.
Gas Laws Study Guide
Answer Section

MULTIPLE CHOICE

    1.    A

    2.    C

    3.    D

    4.    C

    5.    C

    6.    B

    7.    C

    8.    B

    9.    D

    10.    A

    11.    C

    12.    D

    13.    C

    14.    C

    15.    B

    16.    B

    17.    A

    18.    A

    19.    A

    20.    D

    21.    A

    22.    A

    23.    B

    24.    B

    25.    A

    26.    C

    27.    B

    28.    D

    29.    B

    30.    B

    31.    D

    32.    C

    33.    C

    34.    A

    35.    B

    36.    A

    37.    B

    38.    A

    39.    C

    40.    C

    41.    B

    42.    B

    43.    C

    44.    C

    45.    B

    46.    A

    47.    A

    48.    B

    49.    A

    50.    B

    51.    D

    52.    C

    53.    A

    54.    C

    55.    C

    56.    D

    57.    B

    58.    D

    59.    A

    60.    C

    61.    D

    62.    D

    63.    C

    64.    C

    65.    B

    66.    C

    67.    A

    68.    C

    69.    D

    70.    C

    71.    A

    72.    C

    73.    D

    74.    B

    75.    C

    76.    B

    77.    B

    78.    D

    79.    B

    80.    B

    81.    B

    82.    B

    83.    B

    84.    D

    85.    D

    86.    B

    87.    C

    88.    B

    89.    C

    90.    C

    91.    B

    92.    C

    93.    B

    94.    D

    95.    C

    96.    D

    97.    B

    98.    D

    99.    A

    100.    A

    101.    B

    102.    D

    103.    B

    104.    A

    105.    C

    106.    B

    107.    C

    108.    A

    109.    C

    110.    C

    111.    A

    112.    B

    113.    D

    114.    D

    115.    C

    116.    D

    117.    D

    118.    A

    119.    B

    120.    C

    121.    C

    122.    A

    123.    B

    124.    B

    125.    C

    126.    D

    127.    D

    128.    D

    129.    C

    130.    A

    131.    D

    132.    C

    133.    B

    134.    A

    135.    C

    136.    C

    137.    A

    138.    A

    139.    D

    140.    A

    141.    A

    142.    C

    143.    C

    144.    A

    145.    C

    146.    B

    147.    A

    148.    C

    149.    D

    150.    A

    151.    C

    152.    C

    153.    C

    154.    B

    155.    A

    156.    C

    157.    D

    158.    B

    159.    A

    160.    B

    161.    D

    162.    B

    163.    D

    164.    C

    165.    A

    166.    B

    167.    C

    168.    A

    169.    B

    170.    C

    171.    B

    172.    B

    173.    A

    174.    D

    175.    C

    176.    D

    177.    B

    178.    A

    179.    C

    180.    D

    181.    A

    182.    D

    183.    B

    184.    A

    185.    C

    186.    B

    187.    A

    188.    B

    189.    A

    190.    A

    191.    D

    192.    D

    193.    D

SHORT ANSWER

    194.    Gas particles glide easily past one another because the attractive forces between them are insignificant. Because this behavior is similar to liquids, gases are classified as fluids.

    195.    The air pressure at the open end forces the mercury up the tube. A vacuum exists at the closed end so there is no opposing force.

    196.    Standard temperature is 0ºC, and standard pressure is 1 atm. Scientists have agreed upon standard conditions for temperature and pressure to compare volumes of gases.

PROBLEM

    197.    407 m/s



    198.    501 m/s



    199.    1360 m/s



    200.    121 g/mol



    201.    39.7 g/mol



    202.    43.8 g/mol



ESSAY

    203.    A tube filled with mercury is inverted into a pool of mercury. The mercury column falls until the weight of the mercury above the surface of the pool balances the force of the atmosphere on the open surface of the mercury in the pool. As air pressure changes, the height of the mercury column rises or falls.