Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

Densities and speeds of sound for aqueous solutions of sodium benzene sulfonate, sodium p-toluene sulfonate, disodium 1,3-benzene disulfonate, sodium 1-naphthalene sulfonate, and disodium 1,5-naphthalene disulfonate were accurately measured at various concentrations and at (293.15, 303.15, 313.15, 323.15, and 333.15) K. These data were utilized in determining apparent molar volumes, VF, and apparent molar isentropic compressibilities, KSF. VF and KSF values were plotted against concentration according to equations based on the Debye-Hckel theory, and the corresponding infinite dilution values (V0F and K0SF) were determined by extrapolation to zero concentration. Properties at infinite dilution were interpreted in terms of solute-water interactions. The temperature dependence of volumetric data provided the apparent molar isobaric expansivities of benzene and naphthalene sulfonates. A comparison of V0F and K0SF values for certain pairs of systematically chosen benzene and naphthalene sulfonates provided important information about the effects of certain hydrophobic or hydrophilic groups in the structures on the solution behavior of these sulfonates.