Chromisulphuric acids

These acids form dark brown amorphous masses which, in freshly prepared, dil. soln. exhibit the characteristic reactions of neither SO4"—-nor Cr04"—-radicles, slowly decompose when they do show the reactions of these radicles. Arguing by analogy, and from some observations on the heats of neutralization, it is inferred that the constitution of the chromisulphatochromic acids resembles that of the chromisulphuric acids. If the alkali chromates are employed in place of chromic acid in the preparation of the.se products then the corresponding chromisulphatochromates are formed. J. Poizat. studied the action of chromi-mouo-, -di-, and tri-sulphuric acids on hydrogen dioxide. 

According to G. N. Wyrouboff, when an aq. soln. of chromisulphuric acid is heated, a coagulum is formed which he caliod chromium sulphochronuUe, [Cr,02(011)4(802)402(0H)2]Cr2(0H) and which is identical with that obtained by precipi. tating a violet salt of chromium in the cold with sulphochromic acid. If this is maintained for... 

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