Densities and sound velocities of the binary liquid mixtures of sulfolane + aniline, sulfolane +
N,N-dimethylaniline, sulfolane + N,N-diethylaniline over the whole range of composition and their
pure component were measured at temperatures (T = 303.15, 308.15, 313.15 K) and atmospheric
pressure. A high precision vibrating-tube densitometer was used for the measurements. From the
measured values, excess adiabatic compressibility (βs
E), excess sound velocity (uE), excess internal
pressure (Pi
E) and deviation of surface tension (Δγ) were calculated for each of the systems. The excess
properties and surface tension deviation were fitted to the Redlich-Kister equation. All these properties
have been discussed in terms of molecular interactions.