A student took four test tubes I, II, III and IV containing aluminium sulphate, copper sulphate, ferrous sulphate and zinc sulphate solutions, respectively. He placed an iron strip in each of them. In which test tube, a brown deposit is formed?
A student took four test tubes I, II, III and IV containing aluminium sulphate, copper sulphate, ferrous sulphate and zinc sulphate solutions, respectively. He placed an iron strip in each of them. In which test tube, a brown deposit is formed?