Question

What is reactivity series?what happens when iron reacts with copper sulphate solution?

Answer 1

Reactivity series is a series of an arrangement of metals in decreasing order of their reactivity.

When copper sulphate reacts with iron,iron will displace copper from the copper sulphate solution to form ferrous sulphate.
$F{e}_{\left(s\right)}+CuS{O_4}_{\left(aq\right)}\to FeS{O}_{4\left(aq\right)}+C{u}_{\left(s\right)}$