Hydrazine Dithionate, N₂H₄.H₂S₂O₆

Hydrazine Dithionate, N₂H₄.H₂S₂O₆, a polymer of amidosulphonic acid, may be prepared by the interaction of hydrazine sulphate and barium dithionate. It is obtained as large crystals. On evaporation over sulphuric acid it decomposes with separation of sulphuric anhydride and is converted into a mixture of hydrazine sulphate and secondary hydrazine dithionate, (N₂H₄)₂.H₂S₂O₆.