A new volumetric method of cerium determination by thiocyanate

Abstract

A new volumetric method for cerium determination, based on the reduction of ceric sulphate by potassium or ammonium thiocyanate added in excess and the determination of the excess by back-titration as in Volhard's method is developed. One molecule of KCNS reacts with six molecules of Ce(SO4)2; the sulphur atom of the thiocyanate is oxidized to sulphate. Ce... and SO4″ ions in moderate quantities and the usual rare earth impurities in ceric sulphate do not affect the accuracy of the method. The possibility of using ceric sulphate in the determination of small quantities of thiocyanate and in argentometric titration is suggested. © 1953 Indian Academy of Sciences.