Assertion: Oxygen atom in both `O_(2)` and `O_(3)` has oxidation number zero.
Reason: In `F_(2)O`, oxidation number of `O` is `+2`.

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 the oxygen atom in both \( O_2 \) (dioxygen) and \( O_3 \) (ozone) has an oxidation number of zero.

- **Explanation**: In chemistry, the oxidation number of an element in its elemental form is always zero. Since \( O_2 \) and \( O_3 \) are both forms of elemental oxygen, the oxidation number for the oxygen atoms in both molecules is indeed zero.

### Step 2: Analyze the Reason
The reason states that in \( F_2O \) (difluorooxide), the oxidation number of oxygen is +2.

- **Calculation**: To find the oxidation number of oxygen in \( F_2O \), we can set up the equation based on the known oxidation states:
- Let the oxidation number of oxygen be \( x \).
- The oxidation number of fluorine (F) is -1.
- In \( F_2O \), there are two fluorine atoms, so the total contribution from fluorine is \( 2 \times (-1) = -2 \).
- The molecule is neutral, so we set up the equation:
\[ x + (-2) = 0 \]
\[ x - 2 = 0 \]
\[ x = +2 \]
- **Conclusion**: The oxidation number of oxygen in \( F_2O \) is indeed +2.

### Step 3: Conclusion
Both the assertion and the reason are true:
- The assertion is true because the oxidation number of oxygen in \( O_2 \) and \( O_3 \) is zero.
- The reason is also true as the calculation shows that the oxidation number of oxygen in \( F_2O \) is +2.

However, the reason does not explain the assertion because the oxidation state of oxygen in \( F_2O \) does not relate to the oxidation state of oxygen in \( O_2 \) and \( O_3 \).

### Final Answer
The correct option is: **Both assertion and reason are true, but the reason is not the correct explanation of the assertion.**

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