SOLUTIONS MANUAL –
ATKINS' PHYSICAL
CHEMISTRY, 12TH EDITION
BY ATKINS | ALL 19
CHAPTERS COVERED
Solutions Manual – Atkins' Physical Chemistry, 12th
Edition
Comprehensive Practice Exam | 200 Questions with Bolded
Correct Answers & Detailed Rationales
Section 1: Focus 1 – The Properties of Gases (Questions 1–
20)
1. Which law relates pressure and volume of a gas at constant temperature?
A. Charles' Law
B. Boyle's Law
C. Avogadro's Law
D. Gay-Lussac's Law
,Rationale: Boyle's Law states that pressure is inversely proportional to volume at
constant temperature (pV = constant) .
2. A 2.0 L container of gas at 1.0 atm is compressed to 1.0 L at constant
temperature. What is the new pressure?
A. 0.5 atm
B. 1.0 atm
C. 2.0 atm
D. 4.0 atm
Rationale: Using Boyle's Law (P₁V₁ = P₂V₂), pressure doubles when volume is halved at
constant temperature .
3. At constant pressure, which variable is directly proportional to gas volume?
A. Temperature
B. Pressure
C. Moles
D. Density
Rationale: Charles' Law states that gas volume increases linearly with temperature at
constant pressure .
4. A gas has a volume of 3.0 L at 300 K. If heated to 450 K at constant pressure,
what is the new volume?
A. 2.0 L
B. 4.5 L
C. 3.5 L
D. 6.0 L
Rationale: Charles' Law: V₂ = (3.0 × 450) / 300 = 4.5 L .
5. Which gas law involves the relationship between pressure and temperature at
constant volume?
A. Charles' Law
B. Boyle's Law
C. Gay-Lussac's Law
D. Avogadro's Law
,Rationale: Gay-Lussac's Law states that pressure is directly proportional to temperature
at constant volume .
6. One mole of an ideal gas occupies 22.4 L at STP. Which principle is used?
A. Dalton's Law
B. Ideal Gas Law
C. Graham's Law
D. Raoult's Law
Rationale: The Ideal Gas Law (pV = nRT) calculates molar volume at STP .
7. Two gases at the same temperature and pressure have equal volumes. What can
be inferred?
A. Different moles
B. Same number of molecules
C. Different densities
D. Different temperatures
Rationale: Avogadro's Law states equal volumes of gases at the same T and P contain
equal molecules .
8. A gas mixture exerts a total pressure of 3 atm. If one component exerts 1 atm,
what is the partial pressure of the other?
A. 1 atm
B. 2 atm
C. 3 atm
D. 4 atm
Rationale: Dalton's Law: total pressure is sum of partial pressures; 3 − 1 = 2 atm .
9. Gas A effuses twice as fast as gas B at the same temperature. What is true about
their molar masses?
A. M_A = 2 M_B
B. M_B = 4 M_A
C. M_A = 4 M_B
D. M_A = M_B
Rationale: Graham's Law: rate_A/rate_B = √(M_B/M_A). If rate_A = 2 rate_B, then 4 =
M_B/M_A, so M_B = 4 M_A.
, 10. According to the kinetic molecular theory, the average translational kinetic
energy of a gas molecule is:
A. ½mu²
B. (3/2)kT
C. (1/2)kT
D. (3/2)RT
Rationale: The average translational kinetic energy per molecule is (3/2)kT, where k is
Boltzmann's constant. This is independent of molecular mass .
11. In the van der Waals equation of state, (p + a/V_m²)(V_m − b) = RT, the
parameter 'a' accounts for:
A. The finite volume of gas molecules
B. Intermolecular attractive forces
C. The kinetic energy of molecules
D. The pressure of the gas
Rationale: The 'a' parameter accounts for intermolecular attractive forces, while 'b'
accounts for finite molecular volume .
12. The compressibility factor Z for an ideal gas is:
A. Z > 1
B. Z = 1
C. Z < 1
D. Z = 0
Rationale: For an ideal gas, Z = pV_m/RT = 1. Deviations from Z = 1 indicate non-ideal
behavior.
13. The Boyle temperature is the temperature at which:
A. The second virial coefficient B = 0
B. The gas liquefies
C. Z = 0
D. The gas becomes ideal at all pressures
Rationale: At the Boyle temperature, the second virial coefficient B(T) = 0, and the gas
behaves ideally over a range of pressures.
14. Which of the following is NOT a postulate of the kinetic molecular theory?
ATKINS' PHYSICAL
CHEMISTRY, 12TH EDITION
BY ATKINS | ALL 19
CHAPTERS COVERED
Solutions Manual – Atkins' Physical Chemistry, 12th
Edition
Comprehensive Practice Exam | 200 Questions with Bolded
Correct Answers & Detailed Rationales
Section 1: Focus 1 – The Properties of Gases (Questions 1–
20)
1. Which law relates pressure and volume of a gas at constant temperature?
A. Charles' Law
B. Boyle's Law
C. Avogadro's Law
D. Gay-Lussac's Law
,Rationale: Boyle's Law states that pressure is inversely proportional to volume at
constant temperature (pV = constant) .
2. A 2.0 L container of gas at 1.0 atm is compressed to 1.0 L at constant
temperature. What is the new pressure?
A. 0.5 atm
B. 1.0 atm
C. 2.0 atm
D. 4.0 atm
Rationale: Using Boyle's Law (P₁V₁ = P₂V₂), pressure doubles when volume is halved at
constant temperature .
3. At constant pressure, which variable is directly proportional to gas volume?
A. Temperature
B. Pressure
C. Moles
D. Density
Rationale: Charles' Law states that gas volume increases linearly with temperature at
constant pressure .
4. A gas has a volume of 3.0 L at 300 K. If heated to 450 K at constant pressure,
what is the new volume?
A. 2.0 L
B. 4.5 L
C. 3.5 L
D. 6.0 L
Rationale: Charles' Law: V₂ = (3.0 × 450) / 300 = 4.5 L .
5. Which gas law involves the relationship between pressure and temperature at
constant volume?
A. Charles' Law
B. Boyle's Law
C. Gay-Lussac's Law
D. Avogadro's Law
,Rationale: Gay-Lussac's Law states that pressure is directly proportional to temperature
at constant volume .
6. One mole of an ideal gas occupies 22.4 L at STP. Which principle is used?
A. Dalton's Law
B. Ideal Gas Law
C. Graham's Law
D. Raoult's Law
Rationale: The Ideal Gas Law (pV = nRT) calculates molar volume at STP .
7. Two gases at the same temperature and pressure have equal volumes. What can
be inferred?
A. Different moles
B. Same number of molecules
C. Different densities
D. Different temperatures
Rationale: Avogadro's Law states equal volumes of gases at the same T and P contain
equal molecules .
8. A gas mixture exerts a total pressure of 3 atm. If one component exerts 1 atm,
what is the partial pressure of the other?
A. 1 atm
B. 2 atm
C. 3 atm
D. 4 atm
Rationale: Dalton's Law: total pressure is sum of partial pressures; 3 − 1 = 2 atm .
9. Gas A effuses twice as fast as gas B at the same temperature. What is true about
their molar masses?
A. M_A = 2 M_B
B. M_B = 4 M_A
C. M_A = 4 M_B
D. M_A = M_B
Rationale: Graham's Law: rate_A/rate_B = √(M_B/M_A). If rate_A = 2 rate_B, then 4 =
M_B/M_A, so M_B = 4 M_A.
, 10. According to the kinetic molecular theory, the average translational kinetic
energy of a gas molecule is:
A. ½mu²
B. (3/2)kT
C. (1/2)kT
D. (3/2)RT
Rationale: The average translational kinetic energy per molecule is (3/2)kT, where k is
Boltzmann's constant. This is independent of molecular mass .
11. In the van der Waals equation of state, (p + a/V_m²)(V_m − b) = RT, the
parameter 'a' accounts for:
A. The finite volume of gas molecules
B. Intermolecular attractive forces
C. The kinetic energy of molecules
D. The pressure of the gas
Rationale: The 'a' parameter accounts for intermolecular attractive forces, while 'b'
accounts for finite molecular volume .
12. The compressibility factor Z for an ideal gas is:
A. Z > 1
B. Z = 1
C. Z < 1
D. Z = 0
Rationale: For an ideal gas, Z = pV_m/RT = 1. Deviations from Z = 1 indicate non-ideal
behavior.
13. The Boyle temperature is the temperature at which:
A. The second virial coefficient B = 0
B. The gas liquefies
C. Z = 0
D. The gas becomes ideal at all pressures
Rationale: At the Boyle temperature, the second virial coefficient B(T) = 0, and the gas
behaves ideally over a range of pressures.
14. Which of the following is NOT a postulate of the kinetic molecular theory?
