Kinetics and mechanism of electron-transfer reactions of aqueous and co-ordinated thallium(III). Part XII. Reduction of hexa-aquathallium(III) by hydrazine

Abstract

Thallium(III) perchlorate and hydrazine react in aqueous perchloric acid as in equation (i). The kinetic results conform to rate law (ii), where k₂= 8.4 ± 0.3 dm³ mol^–1s^–1 at 8 °C. 2Tl^III+ N₂H₅+→ 2Tl^I+ N₂+ 5H⁺(i)–½d[Tl^III]/dt=k₂[Tl^III][N₂H₅⁺][H⁺]^–1(ii) The energy and entropy of activation associated with k₂ are 138 ± 6 kJ mol^–1 and 259 ± 25 J K^–1 mol^–1 respectively. The rate of reaction is independent of ionic strength, but chloride ion strongly inhibits the reaction.