Question

Beakers A, B, and C contain zinc sulphate, silver sulphate, and ferrous sulphate solutions respectively. Copper filings are added to each beaker. Blue colour will appear in which of the following beakers?

• A. Beaker A
• B. Beaker B
• C. Beaker C
• D. All the beakers

Answer 1

The correct option is B Beaker B

Copper is less reactive than zinc and iron, but is more reactive than silver. Hence, copper displaces silver from its salt solution.

Copper on reaction with silver sulphate forms copper sulphate and silver. The solution colour changes as copper sulphate is blue in colour. The reaction takes place as follows:

$2{\text{AgSO}}_4\text{(aq)}+\text{Cu}\text{(s)}\to 2\text{Ag}\text{(s)}+{\text{CuSO}}_4\text{(aq)}$

Hence colour change will be observed in the case of beaker B.