Which of the following changes the value of the equilibrium constant ?

Options

A. change in concentration
B. change in pressure
C. change in volume
D. None of these

Answer

To determine which of the following changes the value of the equilibrium constant, we need to analyze the effects of various factors on the equilibrium constant (K).

### Step-by-Step Solution:

1. **Understand the Equilibrium Constant (K)**:
The equilibrium constant (K) is a value that expresses the ratio of the concentrations of products to reactants at equilibrium for a given reaction at a specific temperature.

2. **Identify Factors Affecting K**:
The factors that can affect the value of the equilibrium constant include:
- Change in temperature
- Change in concentration
- Change in pressure
- Change in volume

3. **Analyze Each Factor**:
- **Change in Concentration**: Altering the concentration of reactants or products will shift the position of equilibrium but will not change the value of K.
- **Change in Pressure**: Changing the pressure (for gaseous reactions) can shift the equilibrium position but does not affect K.
- **Change in Volume**: Similar to pressure, changing the volume of the system can shift equilibrium but does not change K.

4. **Conclusion on Temperature**:
The only factor that affects the value of the equilibrium constant is a change in temperature.
- For an **exothermic reaction** (releases heat), increasing temperature decreases K.
- For an **endothermic reaction** (absorbs heat), increasing temperature increases K.

5. **Final Answer**:
Therefore, the correct answer is that none of the changes in concentration, pressure, or volume affect the value of the equilibrium constant. The only change that affects K is a change in temperature.

### Final Answer:
None of these changes the value of the equilibrium constant.

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