(a)Metal X is Copper and Metal Y is Sodium. Both produce sulphate salts on reaction.
(b) XSO4 is Copper sulphate, CuSO4 , the salt formed which is blue in colour.
(c) Y2SO4 is Sodium sulphate, Na2SO4 which is a colourless salt.
(d) Z is Barium sulphate, BaSO4 which is a white precipitate formed upon the reaction when barium chloride is added to copper sulphate and turns the solution green
(e) Copper chloride, CuCl2 is the salt having yellowish-brown colour which turns the solution green.