Separation of Sulphates and Polythionates

Separation is possible of mixtures of sulphates, sulphites, per-sulphates and thiosulphates of thiosulphates, di-, tri-, tetra- and pentathionates and of the anions present in Wackenroder s solution. The various oxidation products from reactions of thiosulphate with CI2, Brg, I2 and SO2 can be identified with the help of these separations. The following sequences of migration distances are obtained using the solvents quoted below  

Standard samples 1 pd of 1% solutions of the Na or K salts. The solutions should be freshly prepared each time since they change to some extent on standing. 

Solvents a) methanol-n-propanol-conc. NH4OH-water(60 + 60+6 

Detection a) O.IM AgNOg to which 2N NH4OH has been added so as just to dissolve the first formed precipitate. All anions with reducing properties or containing sulphide yield dark spots. 

The separated substances are extracted from the adsorbent and determined by a conventional method. 

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