A microanalytical determination of sulphur in organic compounds is carried out by decomposing cautiously the material to be analysed in the hydrogen atmosphere on reduced nickel, which absorbs the sulphur completely and changes itself into sulphide, and by determining iodometrically the hydrogen sulphide which is evolved from the reduced nickel when it is dissolved in hydrochloric acid. It was found thus that the nickel catalyst is able to be applied to the organic microanalysis of sulphur.
1. Sulphate is precipitated by benzidine hydrochloride and on resulting precipitate of filtrate the amount of benzidine is determined colorimetrically. From that value, the amount of sulphate is calculated. 2. “Rapid method” is given, which is simple in execution and does not take much time. The purification of benzidine for this method is also given. 3. The methods are applied on urine analyses and seem to be useful especially in clinical works. 4. In ordinary method 2–2.5 mg. H2SO4 per 10 c.c. can be determined; in rapid method 1–1.5 mg. per 5 c.c. is necessary. 5. When any hindering substances are absent, the accuracy of the results always lies within the range of accuracy of colorimetry. In conclusion, the author wishes to express his sincere thanks to Prof. T. Soda for his kind guidance during the work.