CORRELATION OF THE HAMMETT EQUATION WITH THE SOLUBILITY AND DISSOCIATION-CONSTANTS OF BENZOIC-ACID IN AQUO-ETHANOLIC SOLUTIONS

The correlation of solubility and the dissociation constants of benzoi c acids with Hammett equation in aquo-ethanolic solutions has been att empted. The poor correlation of the solubilities with the Hammett equa tion arises from the difference in the factors responsible for solubil isation processes. The dissociation constants in aquo-ethanolic mixtur es can be well correlated with the Hammett equation and rho is found t o vary linearly with the percentage of the organic solvents. The devia tions from linearity at 16, 34 and 64 wt% of ethanol can be correlated with the structural peculiarities of the solvent mixtures.