STUDIES ON SURFACE TENSION OF SYSTEM - BARIUM SOAP-WATER AND PROPANOL-1

The surface tension results of the barium soap solutions in water-propanol-1 mixtures have been explained on the basis of Szyszkowski’s empirical equation: γ = γo (1 + X ln Y) - X γo ln C. The values of the constants X and Y of the equation have been calculated for various soap systems. The constant X is found to be almost independent of the composition of the solvent mixture but it depends to some extent on the chain length of the soap. The values of Y show a marked increase at 50% propanol-1 concentration which confirms that the transition in the nature of the micelles takes place at about 50% propanol-1 concentration. The values of X and Y are suggestive of the size and nature of the micelles, respectively. © 1969, American Oil Chemists’ Society. All rights reserved.