EXCESS VISCOSITY AND COMPRESSIBILITY OF BINARY MIXTURES OF METHANOL WITH ACETONITRILE AND DIMETHYL FORMAMIDE AT DIFFERENT TEMPERATURES

The densities, viscosities and ultrasonic velocities of binary mixtures of methanol with acetonitrile and dimethyl formamide have been determined at 298.15, 303.15, 308.15 and 313.15 K over the whole composition range. From the experimental data the values of compressibility (Ks), excess compressibility (Kse) and excess viscosity (?e¬) have been calculated. The results are discussed and interpreted in terms of molecular package and specific interaction predominated by hydrogen bonding. The data at various temperatures also provide an opportunity to study the effect of temperature on the sign and magnitude of the deviation in viscosity and compressibility. Results show that excess properties are found to be either negative or positive depending on the molecular interactions and the nature of liquid mixtures.