`H_2O_2` is reduced by

Options

A. `O_(3)`
B. acidic `KMnO_(4)` solution
C. lead sulphide suspension in water
D. none of these

Explanation

To determine which substance can reduce hydrogen peroxide (H₂O₂), we need to analyze the options provided. Here’s a step-by-step solution:

### Step 1: Understand the nature of H₂O₂
Hydrogen peroxide (H₂O₂) can act as both an oxidizing agent and a reducing agent depending on the reaction conditions. In this case, we are looking for a substance that can reduce H₂O₂.

### Step 2: Identify the options
We have three options:
1. Ozone (O₃)
2. Potassium permanganate (KMnO₄)
3. Lead sulfide (PbS) suspension in water

### Step 3: Analyze the oxidizing agents
- **Ozone (O₃)**: Ozone is a strong oxidizing agent. It can oxidize other substances but cannot reduce H₂O₂.
- **Potassium permanganate (KMnO₄)**: This is also a strong oxidizing agent and will oxidize other substances rather than reduce H₂O₂.

### Step 4: Evaluate lead sulfide (PbS)
- **Lead sulfide (PbS)**: This compound can act as a reducing agent. When lead sulfide reacts with hydrogen peroxide, it can reduce H₂O₂ to water (H₂O) while itself being oxidized to lead sulfate (PbSO₄).

### Step 5: Write the reaction
The reaction can be represented as follows:
\[ \text{PbS} + \text{H}_2\text{O}_2 \rightarrow \text{PbSO}_4 + \text{H}_2\text{O} \]
In this reaction, the oxidation state of oxygen in H₂O₂ (−1) is reduced to (−2) in water (H₂O), indicating that H₂O₂ is being reduced.

### Conclusion
Thus, the correct answer is that H₂O₂ is reduced by lead sulfide suspension in water.

### Final Answer
H₂O₂ is reduced by lead sulfide (PbS) suspension in water.

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