Caesium sulphites

The normal sulphite, Cs₂SO₃, is prepared by addition of an equivalent proportion of caesium carbonate to an alcoholic solution of the salt saturated with sulphur dioxide. It forms white, readily soluble crystals.

The primary sulphite, CsHSO₃, is prepared by the action of sulphur dioxide on an alcoholic solution of the carbonate. It is a white, crystalline salt, very soluble in water.