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An ideal gas in a closed container is slowly heated. As its temperature increases, which of the following statements are true ? (A) the mean free path of the molecules decreases. (B) the mean collision time between the molecules decreases. (C) the mean free path remains unchanged. (D) the mean collision time remains unchanged.
- (C) and (D)
- (A) and (B)
- (A) and (D)
- (B) and (C)
Correct answer: (A) and (B)
Solution
As the temperature of an ideal gas increases, the kinetic energy of the molecules also increases, leading to more frequent and energetic collisions. This results in a decrease in the mean free path due to the increased number of collisions, and a decrease in the mean collision time as the molecules move faster and collide more often.
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