Thermodynamic Behavior of Mixtures. 4. Mixtures of Methanol with Pyridine and N,N-Dimethylformamide at 25 °C

Ultrasonic velocities ( u ), densities (ρ), viscosities (η), relative permittivities (ε r ), and refractive indices ( n D ) of mixtures of methanol (MeOH) with pyridine and N, N -dimethylformamide (DMF) have been measured at 25 °C. From u, ρ, and η, deviation in isentropic compressibilities ( ), excess volumes ( V E ), and viscosities (Δη) have been computed. From n D and ε r values, the Kirkwood correlation factor, g, has been evaluated. The variation of such properties shows specific interactions between the components of MeOH + pyridine and MeOH + DMF binary mixtures.