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 3CH 2OCH 2CH 2OH + HOCH 2CH 2(OCH 2CH 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.