For the reaction `H_(2)(g)+I_(2)(g)hArr2HI(g)`
the equilibrium constant `K_(p)` changes with

Options

A. Catalyst
B. Temperatue
C. Amounts of `H_(2)and I_(2)`
D. Amount of HI

Answer

To determine how the equilibrium constant \( K_p \) for the reaction \( H_2(g) + I_2(g) \rightleftharpoons 2 HI(g) \) changes, we need to analyze the factors that affect \( K_p \).

### Step-by-Step Solution:

1. **Understanding the Reaction**:
The given reaction is:
\[ H_2(g) + I_2(g) \rightleftharpoons 2 HI(g) \]
This is a gas-phase reaction where hydrogen and iodine gases react to form hydrogen iodide gas.

2. **Defining the Equilibrium Constant**:
The equilibrium constant \( K_p \) for this reaction is defined in terms of the partial pressures of the gases involved:
\[ K_p = \frac{(P_{HI})^2}{(P_{H_2})(P_{I_2})} \]
where \( P_{HI} \), \( P_{H_2} \), and \( P_{I_2} \) are the partial pressures of HI, H2, and I2, respectively.

3. **Factors Affecting \( K_p \)**:
The equilibrium constant \( K_p \) is influenced by several factors, but it is important to note that:
- **Temperature**: \( K_p \) changes with temperature.
- **Concentration**: \( K_p \) is independent of the concentrations of reactants and products at equilibrium.
- **Catalyst**: The presence of a catalyst does not affect the value of \( K_p \); it only speeds up the rate at which equilibrium is reached.
- **Inert Gases**: The addition of inert gases at constant volume does not change \( K_p \).

4. **Conclusion**:
From the analysis, we conclude that the equilibrium constant \( K_p \) changes only with temperature. Therefore, the correct answer to the question is that \( K_p \) changes with temperature.

### Final Answer:
The equilibrium constant \( K_p \) changes with **temperature** only.

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