Abstract
The kinetics of oxidation of [CrIII(H2O)(TOH)], (TOH=N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetate) by periodate in aqueous solutions has been found to obey the following equationRate=\frack2K6[CrIII]T[IVII]T1+[H+]⁄K5+K6[IVII]Twhere k2 is the rate constant for the electron-transfer process, K5 is the equilibrium constant for dissociation of [CrIII(H2O)(TOH)] to [CrIII(OH)(TOH)]−+H+ and K6 is the pre-equilibrium formation constant. The activation parameters are reported. It is proposed that electron transfer proceeds via an innersphere mechanism with the hydroxo ligand of the chromium(III) complex bridging the two reactants.