(i) Add aqueous hydrochloric acid solution to the solution of lead nitrate and solution of zinc nitrate prepared separately. The solution of lead nitrate would give a white precipitate of PbCl2 whereas there would be no reaction with zinc nitrate solution.
Pb2+ + 2Cl- ---> PbCl2(↓)
(ii) Add aqueous solution of silver nitrate (AgNO3) to the solution of sodium chloride and solution of sodium nitrate prepared separately. The solution of sodium chloride would give a white precipitate of AgCl whereas there would be no reaction with sodium nitrate solution.