Name one reaction in which water acts (i) as an oxidising agent and (ii) as a reducing agent.

Explanation

To answer the question about the reactions in which water acts as an oxidizing agent and a reducing agent, we can follow these steps:

### Step 1: Water as an Oxidizing Agent
1. **Identify a Reaction**: One common reaction where water acts as an oxidizing agent is the reaction between sodium metal (Na) and water (H2O).
2. **Write the Reaction**:
\[ 2 \text{Na} + 2 \text{H}_2\text{O} \rightarrow 2 \text{NaOH} + \text{H}_2\text{O}_2 \]
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