THERMODYNAMICS OF DISSOCIATION OF STRONTIUM, BARIUM AND NICKEL CAPROATES IN WATER

The critical micellar concentration (CMC) and thermodynamic parameters (heat Delta H-d, free energy Delta G(d), and entropy Delta S-d, of di ssociation) of aqueous solutions of strontium, barium and nickel capro ates were determined by conductivity measurements. A Kraus and Bray-ty pe expression was used to evaluate molecular conductance at infinite d ilution and theromdynamic parameters. The results confirm that CMC rem ains unaffected by temperature in the range of 25-55 degrees C, and sh ow that the dissociation of soaps is an exothermic reaction and nonspo ntaneous.