assertion : Ozone is a powerful oxidising agent in comparison to `O_(2)`.
reason: `O_(3)` molecules is diamagnetic but `O_(2)^` is paramagnetic.

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 will analyze both the assertion and the reason provided, and then determine their validity and relationship.

### Step 1: Analyze the Assertion
**Assertion:** Ozone is a powerful oxidizing agent in comparison to \( O_2 \).

- Ozone (\( O_3 \)) is indeed a powerful oxidizing agent. This is because it can release nascent oxygen (\( O \)), which is highly reactive and can oxidize other substances. The ability to release nascent oxygen makes ozone a stronger oxidizing agent than molecular oxygen (\( O_2 \)).

**Conclusion:** The assertion is **True**.

### Step 2: Analyze the Reason
**Reason:** \( O_3 \) molecules are diamagnetic but \( O_2 \) is paramagnetic.

- A molecule is considered diamagnetic if it does not have unpaired electrons and is not attracted to a magnetic field. Conversely, a molecule is paramagnetic if it has unpaired electrons and is attracted to a magnetic field.
- \( O_2 \) has two unpaired electrons in its molecular orbital configuration, making it paramagnetic.
- \( O_3 \) has all paired electrons in its molecular orbital configuration, making it diamagnetic.

**Conclusion:** The reason is also **True**.

### Step 3: Determine the Relationship
- While both the assertion and the reason are true, the reason does not explain why ozone is a more powerful oxidizing agent than \( O_2 \). The oxidizing ability is due to the presence of nascent oxygen released during the dissociation of ozone, not due to its magnetic properties.

### Final Conclusion
Since the assertion is true and the reason is true but does not correctly explain the assertion, the correct answer is:

**Option B:** The assertion is true, but the reason is not the correct explanation for the assertion.

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