Assertion (A): The two `Fe` atoms in `FeO_(3)O_(4)` hace different oxidation numbers.
Reason (R ): `Fe^(2+)` ions decolourise `KMnO_(4)` solution.

Options

A. If both `(A)` and `(R )` are correct 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)` and `(R )` are incorrect.

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 two Fe atoms in Fe₃O₄ have different oxidation numbers.

- **Fe₃O₄** is known as magnetite. It can be represented as a combination of FeO (iron(II) oxide) and Fe₂O₃ (iron(III) oxide).
- In Fe₃O₄, one Fe atom has an oxidation state of +2 (from FeO) and the other two Fe atoms have an oxidation state of +3 (from Fe₂O₃).
- Therefore, it is correct to say that the two Fe atoms in Fe₃O₄ have different oxidation numbers.

### Step 2: Analyze the Reason
The reason states that Fe²⁺ ions decolorize KMnO₄ solution.

- KMnO₄ (potassium permanganate) is purple in color due to the MnO₄⁻ ion.
- When Fe²⁺ ions are added to a KMnO₄ solution, they reduce the MnO₄⁻ ions to Mn²⁺ ions, which are colorless. This results in the decolorization of the purple solution.
- Thus, the statement that Fe²⁺ ions decolorize KMnO₄ solution is also correct.

### Step 3: Determine the Relationship Between Assertion and Reason
Both the assertion and the reason are correct; however, the reason does not explain the assertion. The assertion is about the different oxidation states of Fe in Fe₃O₄, while the reason discusses the behavior of Fe²⁺ ions in a reaction with KMnO₄.

### Conclusion
- **Assertion (A)**: True - The two Fe atoms in Fe₃O₄ have different oxidation numbers (+2 and +3).
- **Reason (R)**: True - Fe²⁺ ions do decolorize KMnO₄ solution.
- However, the reason does not explain the assertion.

Thus, the correct answer is that both the assertion and reason are correct, but the reason is not the correct explanation for the assertion.

### Final Answer
Both assertion and reason are correct, but the reason is not the correct explanation for the assertion.

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