Stannic Sulphate

The feebly basic properties of stannic oxide do not admit of the formation of a stable sulphate; and this is shown by the precipitation of stannic hydroxide when sodium sulphate is added to stannic chloride solution. Nevertheless a crystalline salt of the composition Sn(SO₄)₂.2H₂O is obtained when freshly precipitated stannic hydroxide is dissolved in dilute sulphuric acid and the solution is evaporated. The same salt may be obtained from the solution of stannic oxide in concentrated sulphuric acid, and also a basic salt of the composition Sn(SO₄)₂.SnO₂.2H₂O. Both salts are completely hydrolysed by water.