Intermolecular hydrogen bonding of acetic acid in carbon tetrachloride and benzene

Abstract

The hydrogen bonding dimerization of acetic acid in anhydrous CCl 4and benzene solutions at 25° has been investigated by a dilution calorimetric technique. The calorimetric data are analyzed in terms of relative apparent molar enthalpies, Φ L. The values of Φ L are shown to be consistent with the monomer—dimer model. The results lead to the following values of the equilibrium constant (molar concentrations) and standard enthalpy for formation of dimers from monomers: in CCl 4, K 2 = 900 (±100) and Δ H° 2= −8.1 (±0.2)kcal/mole of dimer; in benzene, K 2=270 (±50) and Δ H° 2 = −7.4 (±0.2) kcal/mole of dimer.