Speeds of sound and isentropic compressibilities of (2-ethoxyethanol + ethylene glycol, diethylene glycol, triethylene glycol, and tetraethylene glycol) binary mixtures at 298.15 K

Abstract The speed of sound ( u ) has been obtained at a frequency of 8.3 MHz in {CH 3 CH 2 OCH 2 CH 2 OH + HOCH 2 CH 2 (OCH 2 CH 2 ) n OH}for n  = 0, 1, 2, and 3 over the whole composition range of studied binary liquid mixtures, at T  = 298.15 K. The speed of sound values were combined with those of our previous results for densities and viscosities to obtain isentropic compressibility ( κ s ), free volume ( V f ), and intermolecular free length ( L f ). From all these data excess isentropic compressibility ( κ s E ), excess free volume ( V f E ) and excess intermolecular free length ( L f E ) as well as the deviations of the speed of sound (Δ u ) were obtained. The results are interpreted in terms of molecular interactions occurring in the solutions.