Empirical polarity parameters for some binary solvent mixtures

Abstract

Values of the empirical solvent polarity parameters E_T and Z have been determined as a function of composition for the binary solvent systems 1,2-dibromoethane + 1,2-dibromopropane, acetone + chloroform, acetone + ethanol, ethanol + chloroform and acetone + dichloromethane. For the 1,2-dibromoethane + 1,2-dibromopropane system both E_T and Z are accurately linear (i.e. additive) functions of composition. For the other systems both parameters vary with composition in a strongly non-additive manner, and the deviations from additivity are interpreted in terms of intermolecular interactions. For these systems, in general E_T and Z are not highly correlated, and neither parameter is highly correlated with other macroscopic properties or parameters derived from them.