For the reaction, `2HI(g) rarr H_(2)(g) + I_(2) (g) - Q KJ` , the equilibrium constant depends upon

Options

A. Temperature only
B. Pressure
C. Catalyst
D. Volume

Explanation

To determine what the equilibrium constant \( K \) depends upon for the reaction \( 2 \text{HI}(g) \rightleftharpoons \text{H}_2(g) + \text{I}_2(g) - Q \, \text{kJ} \), we can follow these steps:

### Step 1: Understand the Equilibrium Constant
The equilibrium constant \( K \) for a reaction at equilibrium is a measure of the ratio of the concentrations of products to reactants, each raised to the power of their coefficients in the balanced equation.

### Step 2: Identify Factors Affecting Equilibrium Constant
The equilibrium constant is influenced by several factors, but it is essential to note that it is primarily dependent on temperature. Other factors such as pressure, volume, and the presence of a catalyst do not affect the value of \( K \).

### Step 3: Analyze the Given Reaction
In the reaction provided, \( 2 \text{HI}(g) \rightleftharpoons \text{H}_2(g) + \text{I}_2(g) - Q \, \text{kJ} \), we observe that heat is released, indicating that this is an exothermic reaction.

### Step 4: Conclusion on the Dependence of \( K \)
Since the equilibrium constant \( K \) is only affected by temperature, we conclude that for the given reaction, the equilibrium constant depends solely on temperature.

### Final Answer
The equilibrium constant \( K \) for the reaction \( 2 \text{HI}(g) \rightleftharpoons \text{H}_2(g) + \text{I}_2(g) - Q \, \text{kJ} \) depends only on **temperature**.

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