Key Concepts from Kinetic Theory
* Gas molecules are in constant random motion. They collide with each other and the walls of the container.
* The average kinetic energy of the molecules is proportional to the absolute temperature. This means hotter gases have faster-moving molecules.
* Collisions with the container walls create pressure. The more frequent and forceful the collisions, the higher the pressure.
Explanation
1. Constant Temperature: Since the temperature is constant, the average kinetic energy of the gas molecules remains constant. This means the average speed of the molecules doesn't change.
2. Constant Volume: The container's fixed volume means there's a limited space for the gas molecules to move around in.
3. Balanced Collisions: With constant temperature and volume, the following happens:
* Collision Frequency: The number of collisions between gas molecules and the container walls remains constant. There's a steady rate of collisions because the molecules are moving at a constant speed and are confined to a fixed space.
* Collision Force: Since the average kinetic energy (and therefore speed) of the molecules is constant, the force of each collision with the walls also remains constant.
4. Constant Pressure: The pressure exerted by the gas is directly related to the rate and force of collisions with the container walls. Because both the frequency and force of these collisions remain constant, the pressure remains constant.
In Summary
The constant temperature ensures that the gas molecules maintain a constant average speed, while the constant volume confines them to a fixed space. This results in a constant rate and force of collisions with the container walls, leading to a stable and unchanging pressure.
