Q1) How many moles are in a 0.23 kg sample of carbon
dioxide, CO2? (atomic masses: C = 12 u; O = 16 u)
1) 0.0052
2) 5.2
3) 230
4) 1.1  104
5) none of the above
Q2) Which one of the following factors is directly responsible for
the pressure exerted by a confined gas?
1) the atomic mass of the gas
2) the density of the sample of molecules
3) the temperature of the sample of molecules
4) the collision of gas molecules with the sides of the containing
vessel
5) the average translational kinetic energy of the molecules
Q3) When will a real gas behave most like an ideal gas?
1) at high temperatures and high pressures
2) at low temperatures and high pressures
3) at low temperatures and low pressures
4) at high temperatures and low pressures
Q4) The temperature of an ideal gas is changed from 30oC to
60oC while the volume is kept constant. How does the
pressure of the gas change as the temperature is increased?
1) the pressure is cut in half
2) the pressure doubles
3) the pressure increases but by less than double
4) the pressure increases but by more than double
Q5) Neon gas at 20 oC is confined within a rigid vessel. It is
then heated until its pressure is doubled. What is the final
temperature of the gas?
1) 10 oC
2) 20 oC
3) 40 oC
4) 313 oC
5) 586 oC
Q6) When the temperature of a quantity of gas is increased
1) the pressure must increase.
2) the volume must increase.
3) the pressure and/or the volume must increase.
4) none of the above
Q7) You fill your backpack with snacks for the long flight over to
Europe on your summer vacation. When you take out your bag of
chips mid-flight,
1) it looks just like it did when you packed it at home.
2) it has shrunk and all of your chips are crushed.
3) it has puffed up and looks like it could pop.
Q8) Two identical rooms are connected by an open doorway.
The temperatures in the two rooms are maintained at
different values. Which room contains more air?
1) the room with the higher temperature
2) the room with the lower temperature
3) the room with the higher pressure
4) neither because they both have the same pressure
5) neither because they both have the same volume
Q9) An ideal gas is initially at T = 150 K, p = 2  105 Pa,
and V = 6 cm3. The temperature is then increased to 300 K.
Which of the following might be the pressure and volume of
the final state?
1) p = 1  105 Pa and V = 6 cm3
2) p = 2  105 Pa and V = 3 cm3
3) p = 3  105 Pa and V = 9 cm3
4) p = 3  105 Pa and V = 8 cm3
5) p = 4  105 Pa and V = 12 cm3
Q10) A container with a piston-lid contains an ideal
gas at temperature T = 27 oC (300 K) and a volume
Vo. The temperature is increased to Tf = 127 oC
while the pressure is kept constant. What is the new
volume?
1) Vo
2) (127/27)Vo
3) (4/3) Vo
4) (3/4) Vo
5) None of these.
Q11) An ideal gas in a container with a piston lid has
a pressure po=1atm, volume Vo, and temperature To =
300K. The piston lid is pushed in, reducing the
volume to Vo/2. At the same time, the temperature
is reduced to Tf = 150K. What is the final pressure?
1) 1 atm
2) 2 atm
3) 4 atm
4) 0.5 atm
5) None of these.
constant pressure
Q12) The rms speed of an oxygen molecule at 0o C is 460
m/s. If the molar mass of oxygen is 32 g and that of helium
is 4 g, then the rms speed of a helium molecule at 0o C is:
1) 230 m/s
2) 326 m/s
3) 650 m/s
4) 920 m/s
5) 1300 m/s
Q13) When comparing the root-mean-square speed, vrms, the
average speed, vav, and the most probable speed, vmp, of molecules
in a gas at temperature T, we find that
1) vrms < vav
2) vrms = vav
3) vrms > vav
4) vmp > vav
5) vmp > vrms
Q14) The Maxwellian speed distribution provides a direct
explanation of:
1) thermal expansion
2) the ideal gas law
3) heat
4) evaporation
5) boiling
Q15) For a gas at thermal equilibrium the average speed v, the
most probable speed vp, and the root-mean-square speed vrms are in
the order:
1) vp < vrms < v
2) vrms < vp < v
3) v < vrms < vp
4) vp < v < vrms
5) v < vp < vrms
Q16) The average speed of air molecules at room temperature is
about:
1) zero
2) 2 m/s (walking speed)
3) 30 m/s (fast car)
4) 500 m/s (supersonic airplane)
5) 3  108 m/s (speed of light)
Q17) The mean free path of molecules in a gas is proportional to:
1) the molecular cross-sectional area
2) the reciprocal of the molecular cross-sectional area
3) the root-mean-square molecular speed
4) the square of the average molecular speed
5) the molar mass
Q18) A gas mixture at temperature T consists of molecules
of types 1, 2, and 3, with molecular masses m1 < m2 < m3.
Rank the three types according to (a) average kinetic energy
and (b) rms speed, greatest first.
1)
2)
3)
4)
5)
(a) all tie
(a) all tie
(a) 1, 2, 3
(a) 1, 2, 3
(a) 3, 2, 1
(b) 3, 2, 1
(b) 1, 2, 3
(b) 1, 2, 3
(b) all tie
(b) all tie
Q19) A certain gas has a temperature 200 K and a pressure
2.0  104 Pa. The molecules have a mean free path of 4.0  10-7 m.
If the temperature is raised to 400 K and the pressure is kept
constant, the mean free path is then:
1) 1.0  10-7 m
4) 8.0  10-7 m
2) 2.0  10-7 m
5) 1.6  10-6 m
3) 4.0  10-7 m
Q20) The heat capacity at constant volume and the heat capacity at
constant pressure have different values because:
1) heat increases the temperature at constant volume but not at constant
pressure
2) heat increases the temperature at constant pressure but not at constant
volume
3) the system does work at constant volume but not at constant pressure
4) the system does work at constant pressure but not at constant volume
5) the system does more work at constant volume than at constant pressure
Q21) An ideal gas, with molecular rotation but not
oscillation, loses energy as heat Q. Is the resulting decrease
in the internal energy of the gas greater if the loss occurs in a
constant-volume process or in a constant pressure process?
1) constant-volume process
2) constant-pressure process
3) whatever!
Q22) For constant-volume processes the heat capacity of gas A is greater
than the heat capacity of gas B. We conclude that when they both absorb
the same energy as heat at constant volume:
1) the temperature of A increases more than the temperature of B
2) the temperature of B increases more than the temperature of A
3) the internal energy of A increases more than the internal energy of B
4) the internal energy of B increases more than the internal energy of A
Q23) The figure below shows five paths traversed by a
monatomic gas on a p-V diagram. Rank the paths according
to the change in internal energy of the gas, greatest first.
1) all tie
2) 5, 12, 34
3) 34, 12, 5
4) 1234, 5
5) 5, 1234
Q24) Rank paths 1, 2, and 3 in the figure below according to the
heat transfer to the gas, greatest first.
1) all tie
2) 3, 1, 2
3) 1, 2, 3
4) 3, 2, 1
5) none of the above
Q25) The figure shows the initial state of an ideal gas and an
isotherm through that state. Which of the paths shown result
in an increase in temperature of the gas?
1) 6, 7, and 8
2) 6, 7, 8, and 9
3) 5, 6, 7, and 8
4) 1, 2, 3, and 4
5) 9
Q26) The specific heat of a diatomic gas is greater than the
specific heat of a monatomic gas because:
1) the diatomic gas does more work when energy is absorbed as heat
2) the monatomic gas does more work when energy is absorbed as heat
3) the energy absorbed by the diatomic gas is split among more DOF
4) the pressure is greater in the diatomic gas
5) the monatomic gas cannot hold as much heat
Q27) For a temperature increase of T, a certain amount of an
ideal gas requires 30 J when heated at constant volume and 50 J
when heated at constant pressure. How much work is done by the
gas in the second situation?
1) 0 J
4) 40 J
2) 20 J
5) 50 J
3) 30 J
Q28) In the p-V diagram below, the gas does 5 J of work along
isotherm ab and 4 J of work along adiabat bc. What is Eint if the
gas traverses the straight path from a to c?
1) –4 J
2) –1 J
3) 1 J
4) 4 J
5) 9 J
Q29) A container is divided into two chambers that are separated
by a valve. The left chamber contains one mole of a monatomic ideal gas.
The right chamber is evacuated. At some instant, the valve is opened and
the gas rushes freely into the right chamber. Which one of the following
statements concerning this process is true?
1) Work is done by the gas.
2) The temperature of the gas decreases.
3) The change in the entropy of the gas is zero.
4) The walls of the containing vessel must get colder.
5) The change in the internal energy of the gas is zero.
Q30) In an adiabatic free expansion
1) no heat is transferred between a system and its surroundings.
2) the pressure remains constant.
3) the temperature remains constant.
4) the volume remains constant.
5) the process is reversible.
Q31) In an isothermal process
1) the volume remains constant.
2) the temperature remains constant.
3) no heat is transferred between a system and its surroundings.
4) the pressure remains constant.
5) the internal energy is not constant.
Q32) In an isobaric process
1) the volume remains constant.
2) the temperature remains constant.
3) the pressure remains constant.
4) no heat is transferred between a system and its surroundings.
5) the internal energy is constant.
Q33) In an isochoric process
1) the temperature remains constant.
2) no heat is transferred between a system and its surroundings.
3) the pressure remains constant.
4) the volume remains constant.
5) the internal energy is constant.
Q34) A quantity of an ideal gas is compressed to half its initial
volume. The process may be adiabatic, isothermal, or isobaric.
Rank those three processes in order of the work required of an
external agent, least to greatest.
1) adiabatic, isothermal, isobaric
2) adiabatic, isobaric, isothermal
3) isothermal, adiabatic, isobaric
4) isobaric, adiabatic, isothermal
5) isobaric, isothermal, adiabatic
Q35) In order that a single process be both isothermal and isobaric:
1) one must use an ideal gas
2) such a process is impossible
3) a change of phase is essential
4) one may use any real gas such as N2
5) one must use a solid
Q36) A fixed amount of ideal gas is compressed adiabatically.
Which entry in the table below correctly depicts the sign of the
work done, the change in the internal energy, and the heat
exchanged with the environment?
1)
2)
3)
4)
5)
work done
positive
negative
negative
positive
negative
E
negative
zero
negative
positive
positive
Q
zero
positive
zero
zero
zero
Q37) A fixed amount of ideal gas is compressed isothermally.
Which entry in the table below correctly depicts the sign of the
work done, the change in the internal energy, and the heat
exchanged with the environment?
work done
1) negative
2) positive
3) negative
4) negative
5) positive
E
zero
negative
zero
negative
zero
Q
negative
zero
positive
zero
positive
Q38) An ideal gas is contained in half of a rigid container by a
membrane which bursts; the other half is initially empty. Is the
final temperature of the gas different than the initial temperature?
1) Yes.
2) No.
Q39) As the pressure in an ideal gas is increased isothermally the
average molecular speed:
1) increases
2) decreases
3) increases at high temperature, decreases at low
4) decreases at high temperature, increases at low
5) stays the same
Q40) An ideal gas of N diatomic molecules has temperature T. If
the number of molecules is doubled without changing the
temperature, the internal energy increases by:
1) 0
2) (1/2)NkT
3) (3/2)NkT
4) (5/2)NkT
5) 3NkT
Q41) The principle of equipartition of energy states that the
internal energy of a gas is shared equally:
1) among the molecules
2) between kinetic and potential energy
3) among the relevant degrees of freedom
4) between translational and vibrational kinetic energy
5) between temperature and pressure
Q42) Three gases, one consisting of monatomic molecules, one
consisting of diatomic molecules, and one consisting of polyatomic
molecules, are in thermal equilibrium with each other and remain
in thermal equilibrium as the temperature is raised. All have the
same number of molecules. The gases with the least and greatest
change in internal energy are respectively:
1) polyatomic, monatomic
2) monatomic, polyatomic
3) diatomic, monatomic
4) polyatomic, diatomic
5) monatomic, diatomic