Assertion : Pressure has no effect on the equilibrium reaction :
`2HI(g) hArr H_2(g) + I_2(g)`
Reason : Equilibrium constant of gaseous reaction is independent of pressure.

Options

A. Assertion and reason both are correct statements and Reason is correct explanation for assertion.
B. Assertion and reason both are correct statement but reason is not correct explanation for assertion
C. Assertion is correct statement but reason is wrong statement.
D. Assertion is wrong statement but reason is correct statement

Answer

To solve the given question, we need to analyze the assertion and reason provided regarding the equilibrium reaction:

**Assertion:** Pressure has no effect on the equilibrium reaction:
\[ 2HI(g) \rightleftharpoons H_2(g) + I_2(g) \]

**Reason:** The equilibrium constant of gaseous reactions is independent of pressure.

### Step-by-Step Solution:

1. **Understanding the Reaction:**
The reaction involves 2 moles of hydrogen iodide (HI) gas dissociating into 1 mole of hydrogen (H₂) gas and 1 mole of iodine (I₂) gas. Thus, we have:
- Left side (reactants): 2 moles of HI
- Right side (products): 1 mole of H₂ + 1 mole of I₂ = 2 moles

2. **Applying Le Chatelier's Principle:**
According to Le Chatelier's Principle, if a change is applied to a system at equilibrium, the system will adjust to counteract that change. In the case of pressure changes:
- If the pressure is increased, the equilibrium will shift towards the side with fewer moles of gas to reduce the pressure.
- If the pressure is decreased, the equilibrium will shift towards the side with more moles of gas to increase the pressure.

3. **Analyzing Moles of Gas:**
In this reaction:
- The total number of moles of gas on the left side (reactants) is 2 (from 2HI).
- The total number of moles of gas on the right side (products) is also 2 (1 H₂ + 1 I₂).
Since the number of moles of gas on both sides is equal, an increase or decrease in pressure will not affect the position of equilibrium.

4. **Conclusion on the Assertion:**
Since the number of moles of gas is the same on both sides, the assertion that pressure has no effect on the equilibrium reaction is **correct**.

5. **Understanding the Equilibrium Constant:**
The equilibrium constant (K) for a reaction is defined at a specific temperature and is independent of pressure changes. It only changes with temperature. Therefore, the reason provided is also **correct**.

6. **Evaluating the Relationship Between Assertion and Reason:**
Although both the assertion and reason are correct, the reason does not adequately explain the assertion. The assertion is based on the equality of moles of gas on both sides, while the reason discusses the independence of the equilibrium constant from pressure, which is not directly related to the assertion.

### Final Answer:
Both the assertion and reason are correct, but the reason is not a valid explanation for the assertion.

Thus, the correct option is **B**: Both the assertion and reason are correct, but the reason is not the correct explanation for the assertion.