A: Enthalpy of neutralisation of 1 equivalent each of `HCl ` and `H_(2)SO_(4)` with NaOH is same.
R : Enthalpy of neutralisation is always the heat evolved when 1 mole acid is neutralised by a base.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion , then mark (1)
B. If both Assertion & Reason are true and the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason is false, then mark (3)

Answer

To solve the question, we need to analyze both the assertion (A) and the reason (R) provided.

### Step 1: Understanding the Assertion (A)
The assertion states that the enthalpy of neutralization of 1 equivalent each of HCl and H₂SO₄ with NaOH is the same.

- **Neutralization Reaction**:
- For HCl:
\[ \text{HCl} + \text{NaOH} \rightarrow \text{NaCl} + \text{H}_2\text{O} \]
- For H₂SO₄ (considering 1 equivalent):
\[ \frac{1}{2} \text{H}_2\text{SO}_4 + \text{NaOH} \rightarrow \text{Na}_2\text{SO}_4 + \text{H}_2\text{O} \]

- **Equivalents**:
- 1 mole of HCl provides 1 mole of H⁺ ions.
- 0.5 moles of H₂SO₄ provide 1 mole of H⁺ ions (since it can donate 2 H⁺ ions per mole).

Thus, when we take 1 equivalent of H₂SO₄, we are using 0.5 moles of it, which will also provide 1 mole of H⁺ ions, similar to HCl.

### Step 2: Conclusion for Assertion (A)
Since both HCl and 0.5 moles of H₂SO₄ provide the same amount of H⁺ ions for the reaction with NaOH, the enthalpy of neutralization for both cases will be the same. Therefore, assertion (A) is **True**.

### Step 3: Understanding the Reason (R)
The reason states that the enthalpy of neutralization is always the heat evolved when 1 mole of acid is neutralized by a base.

- **Analysis of Reason (R)**:
- This statement is misleading because the enthalpy of neutralization is defined for the reaction of 1 equivalent of acid with a base, not strictly 1 mole.
- In the case of diprotic acids like H₂SO₄, we can use half a mole to achieve 1 equivalent, which means the statement does not hold true in all scenarios.

### Step 4: Conclusion for Reason (R)
The reason (R) is **False** because it does not account for the fact that different acids can provide different amounts of H⁺ ions, and thus the enthalpy of neutralization can be calculated based on equivalents rather than strictly moles.

### Final Conclusion
- Assertion (A) is **True**.
- Reason (R) is **False**.