Which of the following reagent can convert benzenediazonium chloride into benzene

Options

A. Water
B. Acid
C. Hypophosphorous
D. HCl

Explanation

To solve the question "Which of the following reagent can convert benzenediazonium chloride into benzene?", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Compound**:
- The compound in question is benzenediazonium chloride, which has the formula C6H5N2Cl. It consists of a benzene ring (C6H5) attached to a diazonium group (N2+) and a chloride ion (Cl-).

2. **Understand the Reaction**:
- Benzenediazonium chloride can be converted to benzene through a reduction reaction. This involves removing the diazonium group and replacing it with a hydrogen atom.

3. **Select the Reagent**:
- The reagent that is commonly used for this conversion is hypophosphorous acid (H3PO2). This reagent acts as a reducing agent, facilitating the conversion of the diazonium compound to benzene.

4. **Write the Reaction**:
- The reaction can be summarized as follows:
\[ \text{C6H5N2Cl} + \text{H3PO2} \rightarrow \text{C6H6} + \text{by-products} \]
- Here, C6H6 represents benzene.

5. **Conclusion**:
- Therefore, the correct reagent that can convert benzenediazonium chloride into benzene is hypophosphorous acid (H3PO2).

### Final Answer:
The reagent that can convert benzenediazonium chloride into benzene is **hypophosphorous acid (H3PO2)**.

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