The pressure is exerted by the gas on the walls of the container because

Options

A. It loses kinetic energy
B. It sticks with the walls
C. On collision with the walls there is a change in momentum
D. It is accelerated towards the walls

Explanation

To solve the question "The pressure is exerted by the gas on the walls of the container because," we will analyze the options provided and derive the correct answer step by step.

### Step-by-Step Solution:

1. **Understanding Pressure**:
Pressure is defined as the force exerted per unit area. In the context of gases, this pressure arises due to the collisions of gas molecules with the walls of the container.

2. **Analyzing the Options**:
- **Option A**: "It loses kinetic energy" - This is incorrect because gas molecules do not lose kinetic energy when they collide with the walls; they simply change direction.
- **Option B**: "It sticks with the walls" - This is also incorrect; gas molecules do not stick to the walls; they bounce off after colliding.
- **Option C**: "On collision with the walls, there is a change in momentum" - This option is correct. When gas molecules collide with the walls, they exert a force on the walls due to the change in momentum, which results in pressure.
- **Option D**: "It is accelerated towards the wall" - This is misleading; while gas molecules do accelerate towards the walls, the pressure is not primarily due to this acceleration.

3. **Conclusion**:
The correct answer is **Option C**: "On collision with the walls, there is a change in momentum." This change in momentum leads to the exertion of pressure on the walls of the container.

### Final Answer:
The pressure is exerted by the gas on the walls of the container because **on collision with the walls, there is a change in momentum**.

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