Which of the following salt will evolve sulphur dioxide gas along with formation of yellowish turbidity when treated with dilute `H_(2)SO_(4)` ?

Options

A. Sodium sulphide
B. Sodium sulphite
C. Sodium thiosuphate
D. Sodium sulphate

Explanation

To determine which salt will evolve sulfur dioxide gas along with the formation of yellowish turbidity when treated with dilute `H₂SO₄`, we can analyze each option provided.

### Step-by-Step Solution:

1. **Identify the salts given in the options:**
- Option 1: Sodium Sulfide (Na₂S)
- Option 2: Sodium Sulfide (Na₂S) - repeated
- Option 3: Sodium Thiosulfate (Na₂S₂O₃)
- Option 4: Sodium Sulfate (Na₂SO₄)

2. **Understand the reaction with dilute `H₂SO₄`:**
- We need to find a salt that reacts with dilute sulfuric acid to produce sulfur dioxide (SO₂) gas and a yellowish turbidity.

3. **Analyze each salt:**
- **Sodium Sulfide (Na₂S):**
- When Na₂S reacts with dilute `H₂SO₄`, it produces hydrogen sulfide (H₂S) gas, not sulfur dioxide. Therefore, it does not meet the criteria.

- **Sodium Thiosulfate (Na₂S₂O₃):**
- When Na₂S₂O₃ reacts with dilute `H₂SO₄`, it produces sulfur dioxide (SO₂) gas and elemental sulfur (S), which can cause yellow turbidity:
\[ \text{Na}_2\text{S}_2\text{O}_3 + \text{H}_2\text{SO}_4 \rightarrow \text{SO}_2 + \text{S} + \text{Na}_2\text{SO}_4 + \text{H}_2\text{O} \]
- This reaction produces yellow turbidity due to the formation of sulfur.

- **Sodium Sulfate (Na₂SO₄):**
- Sodium sulfate does not react with dilute `H₂SO₄` to produce sulfur dioxide. It remains unreacted in this context.

4. **Conclusion:**
- The only salt that evolves sulfur dioxide gas and causes yellow turbidity when treated with dilute `H₂SO₄` is Sodium Thiosulfate (Na₂S₂O₃).

### Final Answer:
**The correct option is Sodium Thiosulfate (Na₂S₂O₃).**