THERMODYNAMIC FUNCTIONS FOR TRANSFER OF SOME SUBSTITUTED BENZOIC-ACIDS, PYRIDINECARBOXYLIC ACIDS, AND NAPHTHOIC ACIDS FROM WATER TO METHANOL PLUS WATER MIXTURES AT 35-DEGREES-C

The solubilities of benzoic, 3-methylbenzoic, 4-methylbenzoic, 2-amino benzoic, 3-aminobenzoic, 4-aminobenzoic, 2-nitrobenzoic, 3-nitrobenzoi c, 4-nitrobenzoic, pyridine-2-carboxylic, pyridine-4-carboxylic, 1-anp hthoic, and 2-naphthoic acids have been determined in water and methan ol (1) + water (2) mixtures (x1 = 0, 5.9, 19.6, and 36.0 mol %) at fiv e temperatures, 35, 45, 55, 65, and 75-degrees-C, respectively. From t he solubility data, the values of the free energy of solution of these acids were found, and from these DELTAG(s)-degrees values, the thermo dynamic functions for the transfer of the acids from water to water methanol were derived. The results are discussed on the basis of the s ign of transfer functions and in terms of solute-solvent interactions.