Titrimetric Determination of Thorium(IV) using N-(2-Hydroxyethyl )ethylenediaminetriacetic Acid as Titrant and Pyrocatechol Violet as an Indicator

Abstract

School of Studies in Chemistry, Vikram University. Ujjain-466 010 Manuscript received 2 March 1981, revised 17 August 1981, accepted 10 December 1981 Thorlum(IV) has been determinded by visual titration with N-(2-hydroxyedtyl)ethylenediamlaetrlacetic acid (HEDTA) around _\(p\)H 2.5, using pyrocatechol violet (PCV) as an indicator at room temperature. The colour change is front pink to lemonyellow. The optimum range for the estimation was found to be 6.0 µg to 1.19 mg Tb per ml In a total volume of 75 ml. The relative standard divition for 16 samplls in 2 differance concentrations (I.e. 6.3 µg/ml to 63 µg/mg .this the optimum ranae) was found to be In the range of 1.3% to 0.45%. Tile optimum coadltioas like _\(p\)H concentration of HEDTA, concentration of indicator, temperature were also established and desceribed. The lnterference of foreign Ions was also studied and their tolerance limits were established and described.