Chlorinated Coppers:
Ferrous Sulphate (Coppers) with chlorine is called chlorinated coppers, which is extremely effective in drinking water treatment over a wide range of pH. The relevant reaction follows:
6 FeSO4 + 3Cl2 → Fe2 (SO4)3 + 2FeCl3 (ppt).
2FeSO4 + 3Ca(HCO3)2 + Cl2 → Fe (OH)3 + 2CaSO4 + CaCl4 + 6CO2
(ppt) (ppt)
With hydrated lime, coppers reacts as follows:
FeSO4.7H2O + Ca (OH3)2 → Fe(OH)2 + CaSO4
Fe (OH)2 + O + H2O → Fe (OH)3