Preparation of ferric sulphate
Erlenmeyer flask dry shake 10 g FeSO 4 .7 H 2 O smeared the powder. Pour it 100 g (55 ml) conc. sulfuric acid, cover with a watch glass flask and heat the solution for about an hour. gradually eliminate crystals Fe 2 (SO 4 ) 3 .4 H 2 O. salt sucked through a glass filter and washed with ethanol and ether (thereby remove residual moisture). Drying at 300 ° C in a stream of carbon dioxide obtained anhydrous salt as an off-yellow powder.