Xylenol Orange. An Amperometric Reagent for Trace Estimation of Erbium( III), T erbium(lll) and Dysprosium(IIl)

Department of Chemistry, Dr. Hari Singh Gour Vishwavidyalaya, Sagar-470 003 Manuscript received 13 July 1984, accepted 29 April 1985 Xylenol orange has been successfully employed as an amperometric reagent for precise estimation of some rare earths. Amperometric titration were performed at-1.10 V vs Hg pool, pH - 6.50, ionic strength µ-0.3 and temperature -70\(\underline{+}\)1°. The molar ratio of metal-xylenol orange complexation is found to be 1 :1. Spectrophoto­metric studies also confirmed the said ratio Titrations are not hampered by the presence of fairly large amount of KI, Nal , MgII , ammonium, CoII, MoVI, chloride and chlorate ions The experimental and calculated statistical data support the utility of the method and report the accuracy and precision of the procedure adopted