Peroxylamidosulphonic acid

The blue acid obtained by the reduction of nitroxylsulphonio acid was assumed by P. Sabatier to be a variety of peroxylamidosulphonic acid, but T. Haga, and F. Raschig did not accept this hypothesis. F. Raschig called this acid Nitrosisul-fonsaure, and G. Lunge and E. Berl, Sulfonitronsmre, M. Trautz showed that it... 

P. Sabatier found that when nitric acid or nitrogen oxides are dissolved in sulphuric acid containing sulphur dioxide, and the soln. is exposed to moist air, there are indications of the formation of a dark blue compound. If a mixture corresponding with 4N0+02 is passed into sulphuric acid, sat. with sulphur dioxide, and cooled at 0°, the liquid remains colourless, but when water is added very slowly, a dark blue soln. is formed. Similarly, when a mixture of air and nitric oxide is passed into monohydrated sulphuric acid, sat. with sulphur dioxide, and cooled to 0°, the bluish-violet soln. is formed at once with vigorous eServescence. With more cone, sulphuric acid, the liquid is at first colourless, and slowly develops the bluish-violet colour. It was thought by P. Sabatier that peroxylamidosulphonic acid was formed, but there is no real evidence of this. The blue acid decomposes spontaneously into sulphuric acid, sulphur dioxide, and nitric oxide, but it is more stable than E. Fremy s potassium peroxylamidodisulphonate, and does not decompose rapidly even at 100°. 

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