Question

Copper sulphate is blue and acquires
.... colour when iron fillings are
dipped into it. *
​

Answer 1

When an iron nail is dipped in copper sulphate solution, a brown coating of copper is formed in the surface of iron and the colour of copper sulphate solution changes from blue to pale green. The reaction shows that iron is more reactive than copper because it displaces copper from the copper sulphate solution.

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