Studies on Molecular Interactions of Some Thiocyanate Salts in Coaqueous Solutions of 1,3-Dioxolane + Water by Volumetric, Viscometric, and Speed of Sound Measurements

Abstract

The densities and viscosities of some thiocyanate compounds, viz., ammonium thiocyanate, sodium thiocyanate, and potassium thiocyanate, in 10 %, 20 %, and 30 % by mass of 1,3-dioxolane + water mixtures have been determined at T = (298.15, 308.15, and 318.15) K and p = 0.1 MPa. The speeds of sound of the thiocyanate compounds in 10 %, 20 %, and 30 % by mass of 1,3-dioxolane + water mixtures have also been determined at 298.15 K. Apparent molar volumes (Vϕ), viscosity B-coefficients, and adiabatic compressibility (β) of these electrolytes were obtained from their densities, viscosities, and speed of sound data. The limiting apparent molar volumes (Vϕo) and experimental slopes (Sv*) derived from the Masson equation and the obtained parameters have been interpreted in terms of ion−solvent and ion−ion interactions, respectively. The viscosity data were evaluated by using the Jones−Dole equation. The structure making/breaking capacities of the electrolytes have been inferred from the sign of (δ2ϕVo/δT2)p and dB/dT. The activation parameters of viscous flow for the ternary solutions studied were also calculated and explained by the application of transition state theory.