Assertion : `O_(3)` acts as a powerful oxidising agent.
Reason : `O_(3)` oxidises lead sulphide to lead sulphate and iodide ions to iodine.

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.

Explanation

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

### Step 1: Analyze the Assertion
The assertion states that O₃ (ozone) acts as a powerful oxidizing agent.

- **Explanation**: Ozone is known for its strong oxidizing properties. It can readily accept electrons from other substances, which makes it a potent oxidizer. This is true.

### Step 2: Analyze the Reason
The reason states that O₃ oxidizes lead sulfide (PbS) to lead sulfate (PbSO₄) and iodide ions (I⁻) to iodine (I₂).

- **Explanation**:
1. The reaction of ozone with lead sulfide can be represented as:
\[ \text{PbS} + 4 \text{O}_3 \rightarrow \text{PbSO}_4 + 4 \text{O}_2 \]
In this reaction, lead sulfide is oxidized to lead sulfate, confirming that O₃ can oxidize PbS.

2. The reaction of ozone with iodide ions can be represented as:
\[ 2 \text{I}^- + \text{O}_3 + \text{H}_2\text{O} \rightarrow \text{I}_2 + \text{O}_2 + 2 \text{OH}^- \]
This shows that iodide ions are oxidized to iodine by ozone.

- Both reactions confirm that O₃ can oxidize PbS to PbSO₄ and I⁻ to I₂, making the reason true as well.

### Step 3: Determine the Relationship
Now, we need to determine if the reason is the correct explanation for the assertion.

- The assertion is true because O₃ is a powerful oxidizing agent.
- The reason is also true as O₃ does oxidize PbS to PbSO₄ and I⁻ to I₂. However, the reason does not explain why O₃ is a powerful oxidizing agent; it simply provides examples of its oxidizing ability.

### Conclusion
Both the assertion and reason are true, but the reason is not the correct explanation for the assertion. Therefore, the correct option is:

**Option 2**: Both assertion and reason are true, but the reason is not the correct explanation of the assertion.

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