Volumetric and acoustic properties of two sodium sulfonateresorcin[4]arenes in water and dimethylsulfoxide

Apparent molal volumes, apparent isentropic compressibilities and solvation numbers of two sodium sulfonateresorcin[4]arenes, Na4BRA and Na4SRA in aqueous and DMSO solutions, were determined from density and speed of sound measurements, over the temperature range (278.15 to 308.15) K, at 5 K intervals. The dependence of the volumes on the molality was correlated to the Redlich-Rosenfeld-Meyer equation for aqueous solutions and the Masson type equation for DMSO solutions. The parameters derived from these equations were interpreted according to hydrophobic and hydrophilic hydration and the ion-ion interactions. The standard (infinite dilution) partial molar properties and their dependence on the temperature were determined. In addition, the transfer properties of the ions from DMSO to water were evaluated. The properties calculated are discussed in terms of solute-solvent and solute-solute interactions.