Question

Write one chemical equation for the chemical reaction in which the following has taken place:

Change in colour

Mention colour change along with equation.

Answer 1

The reaction between iron and copper sulphate changes the blue colour of copper sulphate to a pale green.
\[\ce{\underset{Iron}{Fe_{(s)}} + \underset{(blue)}{\underset{Copper sulphate}{CuSO4_{(aq)}}} -> \underset{(pale green)}{\underset{Ferrous sulphate}{FeSO4_{(aq)}}} + \underset{Copper}{Cu_{(s)}}}\]