Investigation of the Dependence of Hypersound Velocity and Thermodynamic Parameters on Viscosity in Solutions

Abstract

Acoustic studies of binary solutions in a wide range of concentration and temperature are of theoretical and applied importance. This is important both from the point of view of the development of the molecular theory of liquid matter and from the constantly growing practical application of mixtures in a number of industries. We have studied hyperacoustic and thermodynamic parameters in aniline-nitrobenzene solutions at various concentrations and temperatures.

Optical methods will give us the opportunity to obtain more complete information about the nature of the change in the free volume between the molecules of liquids. One of these methods is based on the study of the spectra of the Mandelstam-Brillouin scattering of light. As can be seen from the obtained results, with increasing temperature in solutions, the speed and frequency of hypersound decreases, and the adiabatic compressibility calculated by the formula increases. The relationship between study parameters and concentration is characterized by a change in viscosity. In thermal studies, this relationship is also preserved. As the temperature increases, the viscosity of the liquid decreases and, accordingly, the speed and frequency of hypersound decrease, while the adiabatic compressibility increases. By increasing the proportion of aniline in the solution, the hyperacoustic parameters change as a function of the viscosity described by the formula /2/. The change in these values can be explained by a change in the structure and intermolecular interaction in the studied solutions with a change in the state parameters.