Write the reactions involved in the following:
Diazotisation

Explanation

### Step-by-Step Solution for Diazotization Reactions

**Step 1: Reactants Preparation**
- Start with aniline (C6H5NH2) and prepare the diazonium salt using sodium nitrite (NaNO2) and hydrochloric acid (HCl) at a low temperature (0-5 °C).

**Reaction:**
\[ \text{C}_6\text{H}_5\text{NH}_2 + \text{NaNO}_2 + \text{HCl} \rightarrow \text{C}_6\text{H}_5\text{N}_2^+ \text{Cl}^- + \text{H}_2\text{O} \]

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