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 solve the question regarding the dependence of the equilibrium constant for the reaction \( 2HI(g) \rightleftharpoons H_2(g) + I_2(g) - Q \, \text{KJ} \), we can follow these steps:

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

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

### Step 3: Analyze the Given Reaction
For the reaction \( 2HI(g) \rightleftharpoons H_2(g) + I_2(g) \), the equilibrium constant can be expressed as:
\[ K = \frac{[H_2][I_2]}{[HI]^2} \]
This expression shows that the equilibrium constant is a function of the concentrations of the products and reactants at equilibrium.

### Step 4: Conclude the Dependence of \( K \)
Since we established that the equilibrium constant \( K \) is only affected by temperature, we can conclude that the answer to the question is that the equilibrium constant depends on temperature only.

### Final Answer
The equilibrium constant \( K \) for the reaction \( 2HI(g) \rightleftharpoons H_2(g) + I_2(g) - Q \, \text{KJ} \) depends on **temperature only**.

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