The numerical value of the equilibrium constant or any chemical change is affected by changing the

Options

A. concentration of product
B. catalyst
C. concentration of reacting substance
D. temperature

Answer

To solve the question regarding how the numerical value of the equilibrium constant for a chemical change is affected, we can follow these steps:

### Step-by-Step Solution:

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

2. **Factors Affecting Equilibrium Constant**:
The equilibrium constant is influenced by various factors, but it is crucial to identify which of these factors actually affects its numerical value. The options provided are:
- Concentration of product
- Catalyst
- Concentration of the reacting substance
- Temperature

3. **Analyzing Each Option**:
- **Concentration of Product**: Changing the concentration of products does not change the equilibrium constant; it only shifts the position of equilibrium.
- **Catalyst**: A catalyst speeds up the rate of reaching equilibrium but does not change the equilibrium constant itself.
- **Concentration of Reacting Substance**: Similar to the concentration of products, changing the concentration of reactants shifts the equilibrium position but does not affect the equilibrium constant.
- **Temperature**: The equilibrium constant is dependent on temperature. Changes in temperature will change the value of K.

4. **Conclusion**:
Based on the analysis, the only factor that affects the numerical value of the equilibrium constant is temperature. Therefore, the correct answer is **temperature**.

### Final Answer:
The numerical value of the equilibrium constant for any chemical change is affected by changing the **temperature**.

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