Question: What is the primary assumption of the kinetic theory of gases regarding the motion of gas molecules?

Options:

1. Gas molecules are stationary.
2. Gas molecules move in straight lines until they collide.
3. Gas molecules are always in a state of vibration.
4. Gas molecules have a fixed volume.

Correct Answer: Gas molecules move in straight lines until they collide.

Solution:

The kinetic theory assumes that gas molecules move in straight lines until they collide with each other or the walls of the container.