SOLVENT EFFECTS ON THE KINETICS OF AQUATION OF RO(DIETHYLENETRIAMINE)(ETHYLENEDIAMINE)COBALT(III) ION IN MIXED AQUEOUS SOLVENTS

Solvent effects on the kinetics of aquation of [Co(dien)(en)Cl](2+) ha ve been investigated within the temperature range (40-60 degrees C) in acetone-water and ethanol-water media of varying solvent compositions up to 60% by weight of the organic solvent component. The variation o f the activation parameters (Delta G(#), Delta H-#, and Delta S-#) wit h the mole fraction of the organic solvent component was analysed and discussed. The isokinetic plots were linear in both solvent systems an d revealed the existence of compensation effect due to a strong solute -solvent interactions. The correlation of log k with the ionizing powe r (Y) was found to be linear in both solvent mixtures. Moreover, the c orrelation of log k with D-1 was linear in case of ethanol-water mediu m while in case of acetone-water it was nonlinear. (C) 1997 John Wiley C Sons, Inc.