For the reaction `N_(2)O_(4)(g) hArr 2NO_(2)(g)`, which of the following factors will have no effect on the value of equilibrium constant?

Options

A. Temperature
B. Initial concentration of `N_(2)O_(4)`
C. Pressure of catalyst
D. Pressure

Answer

To determine which factors have no effect on the value of the equilibrium constant for the reaction \( N_2O_4(g) \rightleftharpoons 2NO_2(g) \), we need to analyze the options provided:

1. **Temperature**: The equilibrium constant \( K \) is dependent on temperature. Changing the temperature will change the value of the equilibrium constant. Therefore, temperature does affect the equilibrium constant.

2. **Initial concentration of \( N_2O_4 \)**: The equilibrium constant \( K \) is defined in terms of the concentrations of the products and reactants at equilibrium. While changing the initial concentration of \( N_2O_4 \) will shift the position of equilibrium, it does not change the value of \( K \) itself. Thus, the initial concentration of \( N_2O_4 \) has no effect on the equilibrium constant.

3. **Pressure of catalyst**: A catalyst speeds up the rate of reaching equilibrium but does not affect the position of equilibrium or the value of the equilibrium constant. Therefore, the pressure of a catalyst has no effect on the equilibrium constant.

4. **Pressure**: For gaseous reactions, changing the pressure can shift the position of equilibrium according to Le Chatelier's principle, but it does not change the value of the equilibrium constant \( K \). Thus, pressure also has no effect on the equilibrium constant.

### Conclusion:
The factors that have no effect on the value of the equilibrium constant are:
- Initial concentration of \( N_2O_4 \)
- Pressure of catalyst
- Pressure

### Final Answer:
The correct answer is that the initial concentration of \( N_2O_4 \), the pressure of the catalyst, and the pressure itself have no effect on the equilibrium constant.

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