A student addd few pieces of aluminium metal to two test tubes A and B containing aqueous solutions of iron sulphate and copper sulphate. In the second part of her experiment, the added iron metal to another test tubes C and D containing aqueous solutions of aluminium sulphate and copper sulphate.
In which test tube or test tubes will she observe colour change? On the basis of this experiment, state which one is the most reactive metal and why ?

Explanation

To solve the problem, we will analyze the reactions that occur in each test tube when the metals are added to the solutions.

### Step-by-Step Solution:

1. **Identify the Solutions and Metals:**
- Test Tube A: Contains iron(II) sulfate (FeSO₄) - green color.
- Test Tube B: Contains copper(II) sulfate (CuSO₄) - blue color.
- Test Tube C: Contains aluminum sulfate (Al₂(SO₄)₃) - colorless.
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