All sulphateVI and sulphateIVSO32 ionssalts are solubledissolve in water except Calcium sulphateVICaSO4 Calcium sulphateIVCaSO3 Barium sulphateVIBaSO4 Barium sulphateIVBaSO3 LeadII sulphateVIPbSO4 and LeadII sulphateIVPbSO3When a soluble sulphateVISO42 salt like Na2SO4 H2SO4 NH42SO4 or Na2SO3 is added to a salt containing Ca2 Pb2 Ba2 ions a white precipitate is formed