Ultrasonic Studies of Cu(II) Soaps Derived from Mustard and Soya Bean Oils

Abstract

Abstract Ultrasonic velocities have been measured in ternary mixtures containing copper soaps derived from mustard and soya bean in 20% and 40% methanol-benzene mixture to access the effect of polarity of solvent on the micellar features of surfactant. The studies suggest that predomination of benzene (higher percentage of non-polar solvent) play a significant role in compacting the molecular organization of the micelles. From these values, the specific acoustic impedance Z, adiabatic compressibility βad, intermolecular free length Lf, apparent molar compressibility ϕk, molar sound velocity R, primary solvation number Sn have been calculated. The data clearly indicate that the values of u, Z, Sn and R increase whereas the values of βad and Lf decrease consistently with increase of the soap concentration. The critical micelle concentration CMC has also been determined and it has been found that CMC is dependent on the composition of the solvent mixture and composition of the edible oil. The Masson equation has also been applied. The results have been explained on the basis of intermolecular interactions between solvent and solute.