Diffusion rates are affected by :

Options

A. Pressure
B. Temperature
C. Concentration gradient
D. More than one option is correct

Answer

To solve the question regarding the factors affecting diffusion rates, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Diffusion**:
- Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration. This process occurs until equilibrium is reached.

2. **Identifying Factors Affecting Diffusion**:
- There are several factors that can affect the rate of diffusion. The most significant ones include:
- **Concentration Gradient**: The difference in concentration between two areas. A steeper gradient (greater difference) results in a faster diffusion rate.
- **Pressure Gradient**: The difference in pressure between two areas can also influence diffusion, particularly in gases.
- **Temperature**: Higher temperatures increase the kinetic energy of molecules, which can lead to faster diffusion rates.

3. **Conclusion**:
- Based on the above factors, we can conclude that diffusion rates are affected by:
- Concentration Gradient
- Pressure Gradient
- Temperature

4. **Selecting the Correct Option**:
- The question likely provides multiple choices, and since all three factors (concentration gradient, pressure gradient, and temperature) affect diffusion rates, the correct answer would be an option that includes more than one of these factors.

### Final Answer:
The rates of diffusion are affected by concentration gradient, pressure gradient, and temperature. Therefore, the correct option is D (more than one option is correct).

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