Question

When a strip of aluminium metal is dipped in a solution of ferrous sulphate, the pale green colour of the solution fades away. State the conclusion you can draw from this observation. Write the chemical equation for the reaction that occurs in this case.

Answer 1

Observation Conclusion:
The pale green color of ferrous sulfate solution disappears when an aluminum strip is submerged in it, signifying a displacement reaction. This occurs because aluminum (Al) is more reactive than iron (Fe) and consequently displaces iron from the ferrous sulfate solution.

Chemical Equation:
The reaction can be represented by the following chemical equation: \[ \text{Al (s)} + \text{FeSO}_4 \text{(aq)} \rightarrow \text{Fe (s)} + \text{Al}_2\text{(SO}_4)_3 \text{(aq)} \] Details of the reaction:
- Aluminum (Al) replaces iron (Fe) from ferrous sulfate (FeSO₄).
- Iron (Fe) precipitates as a solid, and aluminum sulfate (Al₂(SO₄)₃) is formed in the solution.

Consequently, the observed fading of the pale green color is a result of Fe²⁺ ions being reduced to metallic iron and aluminum being oxidized to Al³⁺ ions, forming aluminum sulfate.