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CHEM 210 Exams- 2 Advanced Practice Questions
and Answers | 100% Pass Guaranteed | Graded
A+
1. Which of the following statements best describes the kinetic molecular theory of gases?
A. Gas particles have strong intermolecular attractions and occupy a significant volume.
B. Gas particles are in constant, random motion and have negligible volume with no
intermolecular forces.
C. Gas particles are stationary and only vibrate in fixed positions.
D. Gas particles have a fixed shape and volume.
☑ Correct Answer: B
☑ Explanation: The kinetic molecular theory assumes gas particles are in constant
random motion, have negligible volume compared to the container, and have no
significant intermolecular forces. Option A describes liquids or solids. Option C describes
solids. Option D describes solids.
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2. A sample of nitrogen gas occupies a volume of 2.50 L at a pressure of 1.20 atm. If the
temperature remains constant, what volume will the gas occupy at a pressure of 0.80
atm?
A. 1.67 L
B. 2.50 L
C. 3.75 L
D. 4.00 L
☑ Correct Answer: C
☑ Explanation: This is an application of Boyle's Law (P1V1 = P2V2). V2 = (P1V1)/P2
= (1.20 atm × 2.50 L) / 0.80 atm = 3.75 L. Option A is incorrect as it divides by the wrong
pressure. Option B is the initial volume. Option D is a miscalculation.
3. A 3.00 L sample of helium gas has a temperature of 25.0 °C. If the pressure is held
constant, what will be the volume of the gas at 100.0 °C?
A. 3.75 L
B. 12.0 L
C. 2.00 L
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D. 3.00 L
☑ Correct Answer: A
☑ Explanation: Charles's Law (V1/T1 = V2/T2) must be used with temperatures in
Kelvin. T1 = 298.15 K, T2 = 373.15 K. V2 = V1 × (T2/T1) = 3.00 L × (373.15/298.15) = 3.75
L. Option B ignores the temperature conversion. Option C is a miscalculation. Option D is
the initial volume.
4. Which of the following is a property of a real gas that deviates from ideal behavior at
high pressure?
A. The gas particles have negligible volume.
B. The gas particles have no intermolecular attractions.
C. The gas particles have significant volume, reducing the available space.
D. The gas particles move in straight lines.
☑ Correct Answer: C
☑ Explanation: At high pressures, real gases deviate from ideal behavior because
the volume of the gas particles themselves becomes significant relative to the container
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volume, reducing the available space. The assumption of negligible volume fails.
Intermolecular attractions also become more significant, which is another deviation.
5. A mixture of gases contains 2.0 mol of O2, 3.0 mol of N2, and 5.0 mol of CO2. If the total
pressure is 10.0 atm, what is the partial pressure of O2?
A. 2.0 atm
B. 3.0 atm
C. 5.0 atm
D. 10.0 atm
☑ Correct Answer: A
☑ Explanation: Dalton's Law of Partial Pressures states P_O2 = X_O2 × P_total.
X_O2 = moles O2 / total moles = 2.0 mol / (2.0 + 3.0 + 5.0) mol = 2.0/10.0 = 0.20. P_O2 =
0.20 × 10.0 atm = 2.0 atm. Options B and C are the partial pressures of N2 and CO2
respectively. Option D is the total pressure.
CHEM 210 Exams- 2 Advanced Practice Questions
and Answers | 100% Pass Guaranteed | Graded
A+
1. Which of the following statements best describes the kinetic molecular theory of gases?
A. Gas particles have strong intermolecular attractions and occupy a significant volume.
B. Gas particles are in constant, random motion and have negligible volume with no
intermolecular forces.
C. Gas particles are stationary and only vibrate in fixed positions.
D. Gas particles have a fixed shape and volume.
☑ Correct Answer: B
☑ Explanation: The kinetic molecular theory assumes gas particles are in constant
random motion, have negligible volume compared to the container, and have no
significant intermolecular forces. Option A describes liquids or solids. Option C describes
solids. Option D describes solids.
,2
2. A sample of nitrogen gas occupies a volume of 2.50 L at a pressure of 1.20 atm. If the
temperature remains constant, what volume will the gas occupy at a pressure of 0.80
atm?
A. 1.67 L
B. 2.50 L
C. 3.75 L
D. 4.00 L
☑ Correct Answer: C
☑ Explanation: This is an application of Boyle's Law (P1V1 = P2V2). V2 = (P1V1)/P2
= (1.20 atm × 2.50 L) / 0.80 atm = 3.75 L. Option A is incorrect as it divides by the wrong
pressure. Option B is the initial volume. Option D is a miscalculation.
3. A 3.00 L sample of helium gas has a temperature of 25.0 °C. If the pressure is held
constant, what will be the volume of the gas at 100.0 °C?
A. 3.75 L
B. 12.0 L
C. 2.00 L
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D. 3.00 L
☑ Correct Answer: A
☑ Explanation: Charles's Law (V1/T1 = V2/T2) must be used with temperatures in
Kelvin. T1 = 298.15 K, T2 = 373.15 K. V2 = V1 × (T2/T1) = 3.00 L × (373.15/298.15) = 3.75
L. Option B ignores the temperature conversion. Option C is a miscalculation. Option D is
the initial volume.
4. Which of the following is a property of a real gas that deviates from ideal behavior at
high pressure?
A. The gas particles have negligible volume.
B. The gas particles have no intermolecular attractions.
C. The gas particles have significant volume, reducing the available space.
D. The gas particles move in straight lines.
☑ Correct Answer: C
☑ Explanation: At high pressures, real gases deviate from ideal behavior because
the volume of the gas particles themselves becomes significant relative to the container
, 4
volume, reducing the available space. The assumption of negligible volume fails.
Intermolecular attractions also become more significant, which is another deviation.
5. A mixture of gases contains 2.0 mol of O2, 3.0 mol of N2, and 5.0 mol of CO2. If the total
pressure is 10.0 atm, what is the partial pressure of O2?
A. 2.0 atm
B. 3.0 atm
C. 5.0 atm
D. 10.0 atm
☑ Correct Answer: A
☑ Explanation: Dalton's Law of Partial Pressures states P_O2 = X_O2 × P_total.
X_O2 = moles O2 / total moles = 2.0 mol / (2.0 + 3.0 + 5.0) mol = 2.0/10.0 = 0.20. P_O2 =
0.20 × 10.0 atm = 2.0 atm. Options B and C are the partial pressures of N2 and CO2
respectively. Option D is the total pressure.
