8611. Sodium Dithionate

Nomenclature

CAS number: 7631-94-9
Dithionous acid disodium salt.
Na2O6S2; mol wt 206.11.
Na 22.31%, O 46.58%, S 31.11%.

Description and references

Prepd according to the equations MnO2 + 2SO2 → MnS2O6 and MnS2O6 + Na2CO3 → MnCO3 + Na2S2O6: de Baat, Rec. Trav. Chim. 45, 237 (1926); Pfanstiel, Inorg. Synth. 2, 170 (1946).

Chemical structure

Derivative

Dihydrate.

Properties

Colorless, water-clear, orthorhombic crystals. Very stable in air. d 2.189. Loses all of its water of crystn at 110°. When heated to 267° it is dissociated into Na2SO4 and SO2. Soly in water at 0°: 6.05% (w/w); at 20°: 13.39%; at 30°: 17.32%. Insol in alc.