Study of thermodynamic properties of aqueous binary mixtures of glycine, l-alanine and β-alanine at low temperatures (T = 275.15, 279.15, and 283.15) K

In the present communication, experimental values of density (ρ) and speed of sound (u) of aqueous solutions of three amino acids, namely glycine, l-alanine and β-alanine at different temperatures i.e.T = (275.15, 279.15, and 283.15) K are reported. From the experimental values, different derived parameters such as apparent molar volume of solute (ϕVϕV), isentropic compressibility of solution (βS), apparent molar isentropic compressibility of solute (ϕKSϕKS) have been calculated. The limiting values of apparent molar volume of solute (ϕV0), apparent molar isentropic compressibility of solute (ϕKS0) and apparent molar expansivity (ϕE0) in the aqueous medium have also been obtained. The temperature coefficients of these limiting properties have also been computed. The results obtained were interpreted in terms of solute–solvent and solute–solute interactions, and structure making and structure breaking abilities of the solute in aqueous medium.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Study of aqueous solutions of amino acids at low temperatures is presented. ► Amino acids are biologically important compounds. ► Different interactions among solute and solvents have been investigated. ► Hydrogen bonding plays pivotal role in these systems.