,CHEM 121 Module 5 Exam Foundations of General
Chemistry w/Lab | Portage | 26/27 Actual (PDF)
1. Which statement correctly describes the relationship between the pressure and volume of a fixed
amount of gas at constant temperature?
A) Pressure and volume are directly proportional.
B) Pressure and volume are inversely proportional.
C) Pressure and volume are independent of each other.
D) Pressure and volume are equal at all conditions.
Correct Answer: Pressure and volume are inversely proportional.
Rationale: Boyle's law states that at constant temperature and fixed moles of gas, the volume of a gas
is inversely proportional to its pressure (PV = constant). Option A describes Charles's law, option C is
incorrect because pressure and volume are related, and option D is not a valid relationship for gases.
2. A gas occupies 2.50 L at 1.00 atm. What volume will it occupy at 2.50 atm if the temperature
remains constant?
A) 1.00 L
B) 2.50 L
C) 6.25 L
D) 0.500 L
,Correct Answer: 1.00 L
Rationale: Using Boyle's law, P₁V₁ = P₂V₂: (1.00 atm)(2.50 L) = (2.50 atm)(V₂). Solving gives V₂ = 1.00 L.
Option B is the initial volume, option C is the product of pressure and volume, and option D is an
incorrect calculation.
3. According to Charles's law, what happens to the volume of a gas when its temperature is increased
at constant pressure?
A) The volume decreases.
B) The volume increases.
C) The volume remains constant.
D) The volume becomes zero.
Correct Answer: The volume increases.
Rationale: Charles's law states that the volume of a fixed amount of gas at constant pressure is
directly proportional to its absolute temperature in Kelvin. As temperature increases, volume
increases. Options A, C, and D contradict this direct relationship.
4. A gas has a volume of 500.0 mL at 25.0°C. What is its volume at 50.0°C if the pressure remains
constant?
A) 542 mL
B) 458 mL
, C) 1000 mL
D) 250 mL
Correct Answer: 542 mL
Rationale: Using Charles's law, V₁/T₁ = V₂/T₂: (500.0 mL / 298.15 K) = (V₂ / 323.15 K). Solving gives V₂ =
542 mL. Option B is the result of an incorrect temperature conversion, and options C and D are
incorrect calculations.
5. Which statement correctly describes Gay-Lussac's law?
A) The pressure of a gas is inversely proportional to its volume at constant temperature.
B) The pressure of a gas is directly proportional to its temperature in Kelvin at constant volume.
C) The volume of a gas is directly proportional to its temperature at constant pressure.
D) The volume of a gas is directly proportional to the number of moles at constant temperature and
pressure.
Correct Answer: The pressure of a gas is directly proportional to its temperature in Kelvin at constant
volume.
Rationale: Gay-Lussac's law (Amontons's law) states that at constant volume and fixed moles, the
pressure of a gas is directly proportional to its absolute temperature. Option A describes Boyle's law,
option C describes Charles's law, and option D describes Avogadro's law.
6. A gas at 2.00 atm and 300.0 K is heated to 450.0 K at constant volume. What is the new pressure?
A) 1.33 atm
Chemistry w/Lab | Portage | 26/27 Actual (PDF)
1. Which statement correctly describes the relationship between the pressure and volume of a fixed
amount of gas at constant temperature?
A) Pressure and volume are directly proportional.
B) Pressure and volume are inversely proportional.
C) Pressure and volume are independent of each other.
D) Pressure and volume are equal at all conditions.
Correct Answer: Pressure and volume are inversely proportional.
Rationale: Boyle's law states that at constant temperature and fixed moles of gas, the volume of a gas
is inversely proportional to its pressure (PV = constant). Option A describes Charles's law, option C is
incorrect because pressure and volume are related, and option D is not a valid relationship for gases.
2. A gas occupies 2.50 L at 1.00 atm. What volume will it occupy at 2.50 atm if the temperature
remains constant?
A) 1.00 L
B) 2.50 L
C) 6.25 L
D) 0.500 L
,Correct Answer: 1.00 L
Rationale: Using Boyle's law, P₁V₁ = P₂V₂: (1.00 atm)(2.50 L) = (2.50 atm)(V₂). Solving gives V₂ = 1.00 L.
Option B is the initial volume, option C is the product of pressure and volume, and option D is an
incorrect calculation.
3. According to Charles's law, what happens to the volume of a gas when its temperature is increased
at constant pressure?
A) The volume decreases.
B) The volume increases.
C) The volume remains constant.
D) The volume becomes zero.
Correct Answer: The volume increases.
Rationale: Charles's law states that the volume of a fixed amount of gas at constant pressure is
directly proportional to its absolute temperature in Kelvin. As temperature increases, volume
increases. Options A, C, and D contradict this direct relationship.
4. A gas has a volume of 500.0 mL at 25.0°C. What is its volume at 50.0°C if the pressure remains
constant?
A) 542 mL
B) 458 mL
, C) 1000 mL
D) 250 mL
Correct Answer: 542 mL
Rationale: Using Charles's law, V₁/T₁ = V₂/T₂: (500.0 mL / 298.15 K) = (V₂ / 323.15 K). Solving gives V₂ =
542 mL. Option B is the result of an incorrect temperature conversion, and options C and D are
incorrect calculations.
5. Which statement correctly describes Gay-Lussac's law?
A) The pressure of a gas is inversely proportional to its volume at constant temperature.
B) The pressure of a gas is directly proportional to its temperature in Kelvin at constant volume.
C) The volume of a gas is directly proportional to its temperature at constant pressure.
D) The volume of a gas is directly proportional to the number of moles at constant temperature and
pressure.
Correct Answer: The pressure of a gas is directly proportional to its temperature in Kelvin at constant
volume.
Rationale: Gay-Lussac's law (Amontons's law) states that at constant volume and fixed moles, the
pressure of a gas is directly proportional to its absolute temperature. Option A describes Boyle's law,
option C describes Charles's law, and option D describes Avogadro's law.
6. A gas at 2.00 atm and 300.0 K is heated to 450.0 K at constant volume. What is the new pressure?
A) 1.33 atm
