How can the following conversions be brought about:
Nitro benzene to benzene diazonium chloride.

Explanation

To convert nitrobenzene to benzene diazonium chloride, we can follow these steps:

### Step 1: Reduction of Nitrobenzene to Aniline
- **Reaction**: Nitrobenzene (C6H5NO2) is reduced to aniline (C6H5NH2).
- **Reagents**: We can use tin (Sn) and hydrochloric acid (HCl) for this reduction.
- **Mechanism**: The nitro group (NO2) is reduced to an amino group (NH2) through the action of the reducing agent.

**Chemical Equation**:
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