According to the kinetic molecular theory, why don't all gas particles move with the same speed at a given temperature?

• A. Because gas particles have a range of kinetic energies due to random collisions.
• B. Because all gas particles are attracted to each other, causing them to slow down.
• C. Because heavier gas particles always move faster than lighter ones.
• D. Because temperature only affects the direction, not the speed, of gas particles.

Answer: (A)

Verified step by step guidance

1. Recall that the kinetic molecular theory describes gas particles as constantly moving in random directions with a variety of speeds.
2. Understand that at a given temperature, the average kinetic energy of gas particles is fixed, but individual particles can have different kinetic energies due to random collisions.
3. Recognize that these collisions cause continuous energy exchange among particles, resulting in a distribution of speeds rather than a single uniform speed.
4. Know that this distribution of speeds is described by the Maxwell-Boltzmann distribution, which shows a range of particle speeds at any temperature.
5. Conclude that because of these random collisions and energy exchanges, gas particles do not all move at the same speed even when the temperature is constant.