What does the kinetic theory of gases state about particle speed during collisions?

The kinetic theory of gases posits that gas consists of a large number of small particles, which are in constant random motion. When these particles collide with each other or with the walls of their container, the kinetic energy is conserved in a perfectly elastic collision. This means that while individual particles may change direction and speed during collisions, the overall total energy of the system remains constant.

In the context of the question, the key point is that the average speed of particles doesn't inherently increase or decrease as a direct result of these collisions. Instead, they can be thought of as maintaining a certain average speed dictated by the temperature of the gas. The speed of individual particles may fluctuate due to their random motion, but the principle of conservation of energy during collisions suggests that there isn't a systematic increase or decrease in speed over time.

This understanding reflects why the average speed remains unchanged in an ideal gas scenario, aligning with the principles established in the kinetic theory of gases. Therefore, the statement that particle speed doesn't change during collisions captures the essence of this theory effectively.