MICELLIZATION AND ACOUSTIC BEHAVIOR OF MANGANESE SOAPS IN MIXED-SOLVENTS

Conductometric and ultrasonic determinations of manganese soaps solutions (laurate and myristate) in a mixture of benzene and methanol (50 % V/V) were used to measure the critical micelle concentration, degree of dissociation, dissociation constant, soap-solvent interaction and various acoustic parameters. Conductometric measurements showed that the soaps behave as simple electrolytes in dilute solutions and the results can be explained in terms of Ostwald's formula and Debye-Huckel's theory of weak electrolytes The results of ultrasonic measurements showed that the ultrasonic velocity, acoustic impedance, molar sound velocity and molar sound compressibility increase, while the adiabatic compressibility, apparent molar compressibility, apparent molar volume, intermolecular free length, available volume, relative association and solvation number decrease with increasing soap concentration. The results confirmed that there is a significant interaction between the soap and solvent molecules in dilute solutions and the soap molecules do not aggregate appreciably below the c. m. c.