The analytical kinetics of the titanium(III)-perchlorate reaction—I: Homogeneous reaction kinetics

Abstract

A spectrophotometric investigation has been made of the analytically relevant kinetics of the titanium(III)-perchlorate reaction in chloride and sulphate media. Sulphate media give better and more reproducible results. The reaction in sulphate medium is first-order in titanium(III) and hydrogen ion, but of fractional order in perchlorate. The pseudo third-order rate constant k 3' for the rate equation ▪ has a value of 4.22 ± 0.15 l 2 mol −2 s −1 at 49 °C. The energy of activation in sulphate medium is 84 ± 4 kJ mol −1, and in chloride medium is 80 ± 12 kJ mol -1. Small amounts of chloride m a sulphate medium, or of sulphate in a chloride medium, retard the reaction. The basis has been laid for a rate-measurement method for determination of perchlorate at low concentrations.