Surface Tension Measurements for Binary Mixtures of Chlorobenzene or Chlorocyclohexane + Tetrahydrofuran at 298.15 K

Abstract

Surface tensions (σ) for the binary mixtures chlorocyclohexane + tetrahydrofuran and chlorobenzene + tetrahydrofuran at 298.15 K and 1.013 bar have been determined as a function of the mole fraction. In order to analyze the surface tension behavior, the extended Langmuir (EL) and Shereshefsky models were used and parameters of the models were obtained for these mixtures. The standard Gibbs energy of adsorption (\( - \Delta G^{\circ} \)) was calculated using both models. The Gibbs energy change for replacing 1 mol of solute with 1 mol of solvent in the surface region (∆GS), and the excess number of molecular layers of solute in the surface region, were calculated using Shereshefsky’s model. The magnitudes of ∆GS and \( - \Delta G^{\circ} \) are discussed in terms of the nature and type of intermolecular interactions in the binary mixtures.