Evolution of solute–solvent interactions for aqueous 1-decyl-3-methylimidazolium bromide, [C10mim] [Br] solutions containing glycine/ glycylglycine through volumetric and acoustic studies

Abstract

• New experimental density and speed of sound data have been collected. • Glycine/glycylglycine thermodynamic properties behaviour in aqueous IL has been examined. • Pair and Triplet interaction coefficient define the solute solvent interactions • The potential of co-solute to make and break structures has been interpreted. Volumetric and compressibility characteristics of ternary systems have been examined at temperatures T = 288.15 K−318.15 K at interval of 10 K and atmospheric pressure using vibrating tube densitometer DSA 5000 in order to investigate the interactions present in aqueous {glycine/glycylglycine + ionic liquid 1-decyl-3-methylimidazolium bromide} solutions. Using the experimental data for density, partial molar volume of transfer ( Δ V ϕ 0 ), limiting apparent molar volume ( V ϕ 0 ) have been computed. On the other hand speed of sound data utilized to calculate partial molar isentropic compression of transfer ( Δ K ϕ , S 0 ) and limiting apparent molar isentropic compression ( K ϕ , s 0 ). The ternary system's apparent molar and partially molar volumetric characteristics show that solute-solvent interactions prevail. The pair and triplet interaction coefficients determined from partial molar volumes of transfer and partial molar isentropic compression of transfer provide an explanation for the dominance of paired interactions.