FIRST AND 2ND DISSOCIATION-CONSTANTS AND RELATED THERMODYNAMIC FUNCTIONS OF ADIPIC ACID IN VARIOUS BINARY METHANOL SOLVENT SYSTEMS/

The First and second dissociation constants of adipic acid were determ ined by EMF measurements in water/methanol mixtures with 0, 30, 50 and 70 wt% organic cosolvent. Measurements were made at four different te mperatures (ranging from 30 to 60 degrees C) using the cell: glass ele ctrode/HCL (m(1)), H2L (m(2)), Na2CO3 (m(3))/AgCl ((s)), Ag. The compu tations of these dissociation constants were based on the method of su ccessive approximation by means of basic programmes. The thermodynamic properties (Delta G degrees, Delta H degrees and Delta S degrees) for first and second dissociation reactions of the acid under study, were computed, analyzed and discussed in terms of solute-solvent interacti ons. (C) 1998 Elsevier Science B.V. All rights reserved.