For an exothermic reaction , temperature increase by `10^@C` , the equilibrium constant will

Options

A. 2 times
B. Same
C. 1/2 times
D. 4 times

Answer

To solve the question regarding the effect of temperature increase on the equilibrium constant for an exothermic reaction, we can follow these steps:

### Step-by-Step Solution

1. **Understand the Reaction Type**:
- We are dealing with an exothermic reaction, which means that heat is released during the reaction. The general form of such a reaction can be represented as:
\[ A \rightleftharpoons B + \text{Heat} \]

2. **Effect of Temperature on Exothermic Reactions**:
- According to Le Chatelier's Principle, if a system at equilibrium is subjected to a change in temperature, the equilibrium will shift in a direction that counteracts the change. For an exothermic reaction, increasing the temperature shifts the equilibrium to the left (towards the reactants).

3. **Change in Concentrations**:
- When the equilibrium shifts to the left, the concentration of the reactants (A) will increase, while the concentration of the products (B) will decrease.

4. **Equilibrium Constant Expression**:
- The equilibrium constant \( K \) for the reaction can be expressed as:
\[ K = \frac{[B]^b}{[A]^a} \]
- Here, \( [B] \) and \( [A] \) are the concentrations of the products and reactants, respectively, and \( a \) and \( b \) are their stoichiometric coefficients.

5. **Effect on Equilibrium Constant**:
- Since the concentration of A increases (due to the shift to the left), and the concentration of B decreases, the value of \( K \) will decrease. This indicates an inverse relationship between temperature and the equilibrium constant for exothermic reactions.

6. **Conclusion**:
- Therefore, when the temperature is increased by \( 10^\circ C \), the equilibrium constant \( K \) for the exothermic reaction will decrease.

### Final Answer:
The equilibrium constant will decrease.