Question

if iron dipped in copper sulphate solution then what would be observed​

Answer 1

No reaction will occur because iron is less reactive than copper

Answer 2

when tron is dipped the color of the CuSo4 solution changes to pale green and the nail is coated with brown deposits. this is because of displacement reaction as Fe is more reactive than Cu.

CuSo4 + Fe ⇒ FeSo4 + Cu

Displaced. Fe Displaces Cu from CuSO4 Hence resulting ferrous sulphate