Assertion (A): HOCl is a stronger acid than HOBr.
Reason (R ): More the electronegativity of the halogen stronger is the acid.

Options

A. If both (A) and (R) are correct, and (R) is the correct explanation of (A)
B. If both (A) and (R) are correct, but (R) is not 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 solve the question, we need to analyze both the assertion (A) and the reason (R) provided.

### Step 1: Analyze the Assertion (A)
The assertion states that HOCl (hypochlorous acid) is a stronger acid than HOBr (hypobromous acid).

- **Explanation**: HOCl and HOBr are both oxyacids of halogens. The strength of an acid is often determined by the stability of its conjugate base after it donates a proton (H⁺).
- When HOCl loses a proton, it forms OCl⁻, and when HOBr loses a proton, it forms OBr⁻.

### Step 2: Analyze the Conjugate Bases
Next, we need to compare the stability of the conjugate bases OCl⁻ and OBr⁻.

- **Stability of Conjugate Bases**: The stability of the conjugate base is influenced by the electronegativity of the halogen.
- Chlorine (Cl) is more electronegative than Bromine (Br). This means that OCl⁻ will be more stable than OBr⁻ because the negative charge on the oxygen in OCl⁻ is better stabilized by the more electronegative chlorine.

### Step 3: Conclusion on Assertion (A)
Since OCl⁻ is more stable than OBr⁻, it follows that HOCl is indeed a stronger acid than HOBr. Therefore, the assertion (A) is **true**.

### Step 4: Analyze the Reason (R)
The reason states that "more the electronegativity of the halogen, stronger is the acid."

- **Explanation**: This statement is also true. Higher electronegativity of the halogen leads to better stabilization of the negative charge on the conjugate base, thereby increasing the acid strength.

### Step 5: Conclusion on Reason (R)
Since the reason correctly explains why HOCl is a stronger acid than HOBr, the reason (R) is also **true** and serves as the correct explanation for the assertion (A).

### Final Conclusion
Both the assertion (A) and the reason (R) are correct, and the reason is the correct explanation of the assertion. Therefore, the correct option is:

**Option 1: If both A and R are correct and R is the correct explanation of A.**

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