Which is correct :-

Options

A. `H_(2)O_(2)` oxidize `Mn^(2+)`
B. `HOCl` reduce `H_(2)O_(2)` in acidic medium
C. Rxn of `KMnO_(4)` with `H_(2)O(2)` in both `(H^(+))` medium `& (OH^(-))` medium give `O_(2)`
D. All

Answer

To solve the question regarding which statement is correct, we will analyze each statement step by step.

### Step 1: Analyze the first statement
**Statement:** H2O2 oxidizes Mn²⁺.

**Explanation:**
- Hydrogen peroxide (H2O2) can act as an oxidizing agent.
- When it reacts with Mn²⁺ in a basic medium (presence of OH⁻), the reaction proceeds as follows:

\[ \text{Mn}^{2+} + \text{H}_2\text{O}_2 + 2 \text{OH}^- \rightarrow \text{MnO}_2 + 2 \text{H}_2\text{O} \]

- In this reaction, the oxidation state of manganese changes from +2 to +4, indicating that Mn²⁺ is oxidized.
- Therefore, this statement is **correct**.

### Step 2: Analyze the second statement
**Statement:** HOCl reduces H2O2 in acidic medium.

**Explanation:**
- When HOCl reacts with H2O2, the products formed are:

\[ \text{HOCl} + \text{H}_2\text{O}_2 \rightarrow \text{H}_3\text{O}^+ + \text{Cl}^- + \text{O}_2 \]

- In this reaction, HOCl is acting as an oxidizing agent because it is reducing H2O2. However, upon further analysis, we find that HOCl itself gets reduced from +1 oxidation state to -1 in Cl⁻.
- Therefore, HOCl does not reduce H2O2; instead, it oxidizes H2O2. Thus, this statement is **incorrect**.

### Step 3: Analyze the third statement
**Statement:** Reaction of KMnO4 with H2O in both acidic and basic medium gives O2.

**Explanation:**
- In acidic medium, the reaction of KMnO4 (MnO4⁻) with water produces:

\[ \text{MnO}_4^- + 8 \text{H}^+ + 5 \text{e}^- \rightarrow \text{Mn}^{2+} + 4 \text{H}_2\text{O} + 2 \text{O}_2 \]

- This indicates that O2 is produced in acidic medium.
- In basic medium, the reaction is:

\[ \text{MnO}_4^- + 2 \text{OH}^- \rightarrow \text{K}_2\text{MnO}_4 + \text{H}_2\text{O} + \text{nascent O} \]

- Here, nascent oxygen is produced, not O2. Therefore, this statement is **incorrect**.

### Conclusion
- The only correct statement is the first one: **H2O2 oxidizes Mn²⁺**.

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