Assertion `(A)`: Ferrocyanide ion oxidises `H_2O_2` to `H_2O`.
Reason `(R)` : Oxidation product of `H_2O_2` is `O_2.`

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) is incorrect, but (R) is correct.

Explanation

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

**Assertion (A)**: Ferrocyanide ion oxidizes \( H_2O_2 \) to \( H_2O \).
**Reason (R)**: Oxidation product of \( H_2O_2 \) is \( O_2 \).

### Step 1: Write the Reaction
The reaction involving ferrocyanide ion (\( Fe(CN)_6^{3-} \)) and hydrogen peroxide (\( H_2O_2 \)) can be represented as follows:

\[ Fe(CN)_6^{3-} + H_2O_2 + OH^- \rightarrow Fe(CN)_6^{4-} + 2H_2O + O_2 \]

### Step 2: Analyze the Oxidation States
- In the reaction, the oxidation state of iron changes from +3 in \( Fe(CN)_6^{3-} \) to +2 in \( Fe(CN)_6^{4-} \).
- The oxidation state of oxygen in \( H_2O_2 \) is -1, and in \( O_2 \) it is 0.

### Step 3: Identify the Type of Reaction
- The change in oxidation state of oxygen from -1 in \( H_2O_2 \) to 0 in \( O_2 \) indicates that \( H_2O_2 \) is being oxidized to \( O_2 \).
- This means that \( H_2O_2 \) is not just being converted to \( H_2O \), but it is actually oxidized to \( O_2 \) in this reaction.

### Step 4: Evaluate the Assertion and Reason
- The assertion states that ferrocyanide ion oxidizes \( H_2O_2 \) to \( H_2O \), which is misleading because the primary oxidation product is \( O_2 \).
- The reason states that the oxidation product of \( H_2O_2 \) is \( O_2 \), which is correct.

### Conclusion
- Since the assertion is incorrect (it misrepresents the primary product of the oxidation), and the reason is correct, the final conclusion is:
- **Assertion is incorrect, Reason is correct.**

### Final Answer
The correct option is: Assertion is incorrect, Reason is correct.

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