Question

Distinguish b/w ferrous sulphate solution and ferric sulpahate solution using sodium hydroxide solution.?

Answer 1

It is quite simple.

(1) A pale green precipitate of ferrous hydroxide is formed when aqueous ammonia (NH4OH) is added to the solution of a ferrous salt.

Ferric salts give a reddish brown precipitate of ferric hydroxide.

(2) A solution of a ferrous salt acidified with dilute sulfuric acid decolourises potassium permanganate when a few drops of the purple solution of the latter are added to it.

Ferric salts do not decolourise KMnO4 as they have no reducing power.