Assertion: `H_(2)SO_(4)` is a weaker acid than `HClO_(4)`.
Reason: `SO_(4)^(2-)` is more stable than `ClO_(4)^(-)` in solution.

Options

A. If both (A) and (R) are true and (R) is the correct explanation of (A)
B. if both (A) and (R) are true but (R) is not correct explanation of (A)
C. If (A) is true but (R) is false
D. If (A) is false but (R) is false

Answer

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

### Step 1: Analyze the Assertion
The assertion states that \( H_2SO_4 \) is a weaker acid than \( HClO_4 \).

- **Explanation**:
- \( HClO_4 \) (perchloric acid) is known to be a strong acid, while \( H_2SO_4 \) (sulfuric acid) is also a strong acid but not as strong as \( HClO_4 \).
- The strength of an acid is often determined by the stability of its conjugate base after it donates a proton (H⁺).

### Step 2: Compare the Acidity
We need to understand why \( HClO_4 \) is stronger than \( H_2SO_4 \).

- **Factors Affecting Acidity**:
1. **Electronegativity of the Central Atom**: Higher electronegativity of the central atom leads to stronger acids.
- Chlorine (in \( HClO_4 \)) is more electronegative than sulfur (in \( H_2SO_4 \)).
2. **Oxidation State**: Higher oxidation states of the central atom generally lead to stronger acids.
- The oxidation state of Cl in \( HClO_4 \) is +7, while the oxidation state of S in \( H_2SO_4 \) is +6.

Thus, the assertion is **true**.

### Step 3: Analyze the Reason
The reason states that \( SO_4^{2-} \) is more stable than \( ClO_4^{-} \) in solution.

- **Explanation**:
- To evaluate this, we need to consider the stability of the conjugate bases \( SO_4^{2-} \) and \( ClO_4^{-} \).
- The stability of these ions can be assessed by looking at their resonance structures.
- \( ClO_4^{-} \) has more resonance structures compared to \( SO_4^{2-} \), which makes it more stable.

Thus, the reason is **false**.

### Conclusion
- The assertion is true: \( H_2SO_4 \) is a weaker acid than \( HClO_4 \).
- The reason is false: \( SO_4^{2-} \) is not more stable than \( ClO_4^{-} \).

### Final Answer
The correct option is: Assertion is true, Reason is false.

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