Assertion (A): `S` reacts with `SO_(3)^(2-)` and forms `S_(2)O_(3)^(2-)`
Reason (R) : `S` is electorn deficient and acts and acid and `SO_(3)^(2-)` is a base in terms of Lewis acid theroy.

Options

A. If both (A) and (R) are correc, 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.

Explanation

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

### Step 1: Understand the Assertion (A)
The assertion states that sulfur (S) reacts with the sulfite ion (SO₃²⁻) to form the thiosulfate ion (S₂O₃²⁻).

- **Chemical Reaction**:
\[ S + SO₃^{2-} \rightarrow S₂O₃^{2-} \]

### Step 2: Analyze the Reason (R)
The reason states that sulfur is electron deficient and acts as a Lewis acid, while the sulfite ion (SO₃²⁻) acts as a Lewis base.

- **Lewis Acid-Base Theory**:
- A Lewis acid is a species that can accept an electron pair.
- A Lewis base is a species that can donate an electron pair.

### Step 3: Determine the Electron Configuration of Sulfur
Sulfur has an atomic number of 16, and its electronic configuration is:
\[ 1s^2 2s^2 2p^6 3s^2 3p^4 \]
- This shows that sulfur has vacant d-orbitals, allowing it to accept electron pairs.

### Step 4: Identify the Nature of the Reaction
- In the reaction, sulfur (S) accepts a lone pair from the sulfite ion (SO₃²⁻), which has a lone pair on the sulfur atom in the ion.
- Thus, sulfur acts as a Lewis acid, and SO₃²⁻ acts as a Lewis base.

### Step 5: Conclusion
Both the assertion and the reason are correct. The reason correctly explains why the assertion is true.

### Final Answer
Both A and R are correct, and R is the correct explanation of A. Therefore, the answer is option 1.

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