Question

Vishakha takes a few wire pieces made up of different metals and places them in a blue solution of copper sulphate. What changes does she observe in the colour of the solutions present in beakers I, II, and III? Which type of change is occur in which beaker?

Answer 1

As iron is more reactive than copper, it displaces copper from copper sulphate solution. A green solution of iron sulphate is formed.
$Fe+CuS{O}_4\to FeS{O}_4+Cu$

Silver and gold are less reactive than copper. So, they do not displace copper from copper sulphate solution. Hence, the solution remains blue in colour.