Why does the colour of copper sulphate solution change when an iron nail is dipped in it?

Explanation

### Step-by-Step Solution:

1. **Identify the Reactants:**
- The reactants in this scenario are copper sulfate (CuSO₄) and iron (Fe). Copper sulfate is a blue solution, and iron is a metal.

2. **Understand the Reaction:**
- When an iron nail is dipped into the copper sulfate solution, a chemical reaction occurs. This is a displacement reaction where a more reactive metal (iron) displaces a less reactive metal (copper) from its compound.

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