The density, dynamic viscosity and kinematic viscosity of protic polar solvents (pure and mixed systems) studies: A theoretical insight of thermophysical properties

The densities (ρ) and viscosities (η) have been studied for pure and mixed systems of protic polar solvents water, methanol, ethanol and propan-1-ol for entire composition range at temperature from 293 K to 343 K in 5 K intervals at atmospheric pressure. With increase in temperature the density values as well as the dynamic viscosity values were decrease. The obtained values are used to calculate the excess properties such as excess molar free volume (VE), thermal expansion coefficient (α), excess thermal expansion coefficient (αE), viscosity deviation (Δη) and excess Gibb's free energy (ΔG⁎E) for the activation of viscous flow for mixed systems. The calculated excess properties of binary mixtures were correlated with Redlich-Kister type polynomial equation by least square regression method and fitting parameters were found for all binary systems. The temperature dependence of viscosities for mixed systems has been explained using Arrhenius type equation of Newtonian classic solvents and Eyring transition state equation. The thermodynamic parameters were also evaluated for mixed systems which show the thermal stability of system.