Zinc chloride and zinc sulphate. Watchglasses and containers of anhydrous zinc chloride (ZnCl2, left) and hydrated zinc sulphate (ZnSO4.7H2O, right). Warning symbols are shown on the containers, indicating that the zinc chloride is corrosive, and that the zinc sulphate is a skin irritant. Zinc chloride is used in chemical laboratories to catalyse organic reactions, and is used in industry to clean metal oxide coatings. Zinc sulphate has a wide range of uses, in paints, fertilisers, animal feeds, preservatives and medical drugs.