Hydroxynitrilo-iso-disulphonates

T. Haga did not obtain barium hydroxynitrilo-iso-disulphonate in a state suited for a satisfactory determination of the nature of the salt. The evaporation of a soln. of the ammonium salt with excess of barium hydroxide in a vacuum over sulphuric acid to a small volume removed all ammonia. After removal of the excess of barium hydroxide by carbon dioxide, the filtered soln. was further evaporated in the desiccator. First a viscid and then a bulky, friable, porous mass, devoid of crystalline character, were obtained. The latter was not quantitatively analyzed, but it yielded, when hydrolyzed, barium sulphate and hydroxylamine sulphate in crystals, which were further identified by a very satisfactory acid determination. The product was therefore undoubtedly a barium iso-salt. By using less barium hydroxide, crystallized ammonium barium hydroxynitrilo-iso-disulphonate, 6 (NH4S03)0.NH(NH4S03). Ba(S03)20NH, was formed. 

---