Assertion (A): Poistive catalyst lowers the activation energy of the reaction whereas the heat of reaction remains same.
Reason (R ): The heat of reaction is equal to the difference between activation energies for forward and backward reactions.

Options

A. If both `(A)` and `(R )` are correct, and `(R )` is the correct explnation of `(A)`.
B. If both `(A)` and `(R )` are correct, but `(R )` is noth the correct explanation of `(A)`.
C. If `(A)` is correct, but `(R )` is incorrect.
D. If `(A)` is incorrect, but `(R )` is correct.

Answer

To analyze the given assertion and reason, we can break down the concepts involved step by step.

### Step 1: Understanding the Assertion (A)
The assertion states that a positive catalyst lowers the activation energy of a reaction while the heat of reaction remains the same.

**Explanation:**
- A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process.
- A positive catalyst specifically lowers the activation energy (Ea) required for the reaction to proceed.
- Importantly, the heat of reaction (ΔH), which is the difference in energy between the reactants and products, does not change because the catalyst does not alter the overall energy change of the reaction.

### Step 2: Understanding the Reason (R)
The reason states that the heat of reaction is equal to the difference between the activation energies for the forward and backward reactions.

**Explanation:**
- The heat of reaction (ΔH) can indeed be expressed as the difference between the activation energy of the backward reaction (Ea,backward) and the activation energy of the forward reaction (Ea,forward):
\[ ΔH = Ea,backward - Ea,forward \]
- This relationship holds true regardless of whether a catalyst is present.

### Step 3: Evaluating the Assertion and Reason
Now, we need to evaluate the correctness of both the assertion and the reason.

1. **Correctness of Assertion (A)**: True. A positive catalyst lowers the activation energy while the heat of reaction remains unchanged.
2. **Correctness of Reason (R)**: True. The reason correctly describes the relationship between the activation energies and the heat of reaction.

### Step 4: Conclusion
While both the assertion and reason are true, the reason does not adequately explain the assertion. The assertion is about the effect of a catalyst on activation energy and heat of reaction, while the reason discusses the relationship between activation energies and heat of reaction without linking it to the role of a catalyst.

### Final Answer
- **Assertion (A)**: True
- **Reason (R)**: True
- **Conclusion**: Both are correct, but the reason does not explain the assertion adequately.

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