Thermodynamic, acoustic, viscometric properties and related excess parameters of aqueous triethanolamine and triethanolamine in the presence of 1% and 5% aqueous L-Ascorbic acid solution

This study investigates the behavior of triethanolamine (TEA), a surface-active emulsifying agent, in aqueous binary (TEA + water) and ternary mixtures with 1% and 5% aqueous L-ascorbic acid (L-AA) solutions. It examines the effects of composition and temperature on key physical properties, including densities , speed of sound  and viscosities . From the experimental data, we derived excess and deviation functions such as, excess molar volume ( ), excess isentropic compressibility ( ), excess partial molar compressibility ( ), excess speed of sound ( ), excess intermolecular free length ( ),  isobaric thermal expansion coefficient ( ), specific acoustic impedance ( ) , Relative association (RA) , excess Gibbs free energy of activation for viscous flow ( ), viscosity deviation ( ), activation energy ( ). These results were fitted to Redlich-Kister polynomial equations to determine the coefficients and standard errors. The results reveal the nature and strength of intermolecular interactions in these mixtures.