Excess Acoustical and Volumetric Properties and Theoretical Estimation of Ultrasonic Velocities in Binary Liquid Mixtures of 2-Chloroaniline with Acrylic Esters at 308.15 K

Abstract

The ultrasonic velocities (u) and densities (ρ) for three binary mixture systems of 2-chloroaniline (CA) with ethyl acrylate (EA), butyl acrylate (BA), and 2-ethylhexyl acrylate (EHA) were measured over the entire mole fraction range at the temperature 308.15 K, including those of pure liquids. From these data, the deviations in ultrasonic velocity (Δu), the excess molar volumes (\(V_{\mathrm{m}}^{\mathrm{E}}\)), deviations in excess molar volume (\(\delta V_{\mathrm{m}}^{\mathrm{E}}\)), deviations in isentropic compressibility (ΔkS), excess intermolecular free lengths (\(L_{\mathrm{f}}^{\mathrm{E}}\)), and excess acoustic impedances (ZE) have been calculated. The variations of these properties with solution composition are discussed in terms of molecular interactions among unlike molecules of the mixtures. The excess and deviation functions have been fitted to Redlich-Kister type polynomials and the corresponding standard deviations σ(YE) have been calculated. The deviations and excess values were plotted against the mole fraction of CA over the whole composition range. The \(V_{\mathrm{m}}^{\mathrm{E}}\) and ΔkS values are negative in the EA + CA and BA + CA systems but are positive in the EHA + CA system, which indicates the presence of specific interactions between unlike molecules. Further, theoretical values of the sound velocity in these mixtures have been evaluated using various theories and have been compared with experimental sound velocities to verify the applicability of such theories to the investigated systems. Two types of polynomial equations, f(x) and g(x), have been fitted to experimental values of ultrasonic velocities. The sound velocities obtained by these polynomials have extremely small deviations from the experimental values.