Assertion : Heat of neutralisation of `HNO_(3)` and `NaOH` is same as that of HCl and KOH.
Reason : Both `HNO_(3)` and HCl are storng acids and NaOH and KOH are strong bases.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understand the Assertion**:
- The assertion states that the heat of neutralization of HNO₃ (nitric acid) and NaOH (sodium hydroxide) is the same as that of HCl (hydrochloric acid) and KOH (potassium hydroxide).

2. **Define Heat of Neutralization**:
- Heat of neutralization is defined as the change in enthalpy that occurs when one equivalent of an acid reacts with one equivalent of a base to form water and a salt.

3. **Identify the Types of Acids and Bases**:
- Both HNO₃ and HCl are classified as strong acids, and both NaOH and KOH are classified as strong bases.

4. **Properties of Strong Acids and Bases**:
- Strong acids and bases completely ionize in a dilute solution. This means that when they react, they fully dissociate into their ions (H⁺ from the acid and OH⁻ from the base), leading to a complete neutralization reaction.

5. **Constant Heat of Neutralization**:
- The heat of neutralization for strong acids and strong bases is constant and typically around -57.1 kJ/mol for the reaction between a strong acid and a strong base. This is because the same amount of energy is released when H⁺ ions from the acid combine with OH⁻ ions from the base to form water.

6. **Evaluate the Assertion**:
- Since both pairs (HNO₃ and NaOH, HCl and KOH) consist of strong acids and strong bases, the assertion is correct: the heat of neutralization for both pairs is indeed the same.

7. **Understand the Reason**:
- The reason states that both HNO₃ and HCl are strong acids, and NaOH and KOH are strong bases. This is a true statement and explains why the heat of neutralization is the same for both reactions.

8. **Conclusion**:
- Since both the assertion and the reason are true, and the reason correctly explains the assertion, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer:
Both assertion and reason are true, and the reason is the correct explanation of the assertion.

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