Thermodynamic behaviour of mixtures. Part 2.—Mixtures of acetonitrile with β-picoline, γ-picoline, 2,6-lutidine, isoquinoline and benzene at 25 °C

Abstract

Ultrasonic velocities (u), densities (ρ), static relative permittivities (ε) and refractive indices (n_D) of mixtures of acetonitrile (AN) with β-picoline, γ-picoline, 2,6-lutidine, isoquinoline and benzene have been measured over the entire composition range at 25 °C. Intermolecular interaction parameters, such as the molar sound velocity (u_m) and the solvation number of the co-solvent (N_c) have been calculated for all the binary mixtures. The partial molar volumes (V⁰) and the partial isentropic compressibilities (κ⁰_S) at infinite dilution have been calculated for all the co-solvents as well as for AN. Excess properties, such as the excess isentropic compressibility (κ^E_S), volume (V^E), relative permittivity (Δε), molar polarisation (P^E) and molar refraction (R^E) have also been computed for these binary mixtures. Weak specific interactions are present between the components of AN–β-picoline and AN–γ-picoline in comparison to all other AN–base mixtures.