Thermodynamics of dissociation of strontium, barium and nickel caproates in water

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 dissociation) of aqueous solutions of strontium, barium and nickel caproates were determined by conductivity measurements. A Kraus and Bray-type expression was used to evaluate molecular conductance at infinite dilution and theromdynamic parameters. The results confirm that CMC remains unaffected by temperature in the range of $25-55^circ C$, and show that the dissociation of soaps is an exothermic reaction and nonspontaneous.

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