Sodium pentathionate has not been obtained in the pure state, but is said to be one of the products of the decomposition of acid solutions of sodium thiosulphate, the sulphur dioxide liberated reacting with the thiosulphate:
5Na2S2O3 + 3SO2=2Na2S2O6 + 3Na2SO3.
It is also said to react with sodium sulphite, yielding the trithionate and thiosulphate:
Na2S5O6+2Na2SO3=Na2S3O6+2Na2S2O3. |