Chemical

Formula

Theoretical Yield (%)

Solubility (mg/100 mL)

Sulphur dioxide

SO₂

100.0

11 at 20 ^oC

Sodium sulphite anhydrous

Na₂SO₃

50.8

28 at 40 ^oC

Sodium sulphite (heptahydrate)

Na₂SO₃ @7H₂O

25.4

24 at 25 ^oC

Sodium hydrogen sulphite

NaHSO₃

61.6

300 at 20 ^oC

Sodium metabisulphite

Na₂S₂O₅

67.4

54 at 20 ^oC

Potassium metabisulphite

K₂S₂O₅

57.6

25 at 0 ^oC