Precise Coulometric Titrations of Potassium Dichromate
نویسندگان
چکیده
This paper reports results of a continuing investigation to evaluate coulometric methods of analysis and to develop highly precise and accurate analytical methods for important materials, based upon this technique. Earlier papers described the coulometric titrations of acids and bases [1] 1 and of halides [2]. The present research is concerned with a typical oxidation-reduction titration, the analysis of potassium dichromate. The application of constant-current coulometric titrations to the analysis of dichromate is not novel [3, 4, 5], but highly precise and accurate results have not been reported. The method developed in the present investigation consists of the reduction of dichromate with electrogenerated ferrous ion. The technique and procedure have been refined to permit results reliable to a few parts in 100,000, which are about two orders of magnitude better than those reported by previous investigators.
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