Question

when iron nail is kept in the solution of copper sulphate, then after the reaction what would be in the solution and what would be precipitated

Answer 1

When iron nail is kept in the solution of copper sulphate a displacement reaction will take place and Iron will displace Copper from its salt solution and Copper (brown flake) precipitation will be out.

Fe+CuSo4------ FeSo4 + Cu

Here, Cu (brown flake) is a precipitation.