Experimental densities, dynamic viscosities, speeds of sound, and relative permittivities for six binary mixtures of water + alkanediols (propane -1,2-and -1,3-diol and butane-1,2-, -1,3-, -1,4-, and -2,3-diol) were measured across the whole composition range and in the temperature range (298.15 to 338.15) K. The deviations in dynamic viscosities, excess isentropic compressibilities, and deviations in relative permittivities were also calculated and fitted to a Redlich-Kister type equation. The partial molar volumes at infinite dilution for the water in six binary mixtures and the differences in these values among various diol isomers were calculated and examined to ascertain structural information on the water molecules around various diols. The variation of the Kirkwood correlation factor was also examined across the whole composition range of the mixtures.

Experimental densities, ρ, viscosities, η, speeds of sound, υ, and relative permittivities, ε r, for three binary mixtures of water + 2-pyrrolidinone, + 1-methyl-2-pyrrolidinone, and + 1-vinyl-2-pyrrolidinone were measured over the entire composition range and at different temperatures. The variations of ρ, η, and υ with water mole fractions were typical of systems which show large nonidealities. The excess molar volumes, , excess isentropic compressibilities, , and deviations in dynamic viscosities, δη, and relative permittivities, δε r, were calculated, and their compositional variation was mathematically represented by a Redlich−Kister type equation. The partial molar volumes of water at infinite dilution, , were calculated from the smoothed values of three binary mixtures at different temperatures. The variation of the Kirkwood correlation factor, g K, was examined across the entire composition range. The analysis of these functions revealed that both hydrophobic and hydrophilic hydrations are responsible for the complex nature of the thermophysical behavior in these mixtures.

Isothermal mutual diffusion coefficients (interdiffusion coefficients) were measured for ternary aqueous mixtures of NaCl and Na2SO4 at a constant total molarity of 1.000 mol·dm-3 and 298.15 K. Measurements were performed using Rayleigh interferometry with computerized data acquisition at NaCl molarity fractions of z 1 = 1, 0.90, 0.75, 0.50, 0.25, and 0. Densities of the solutions were measured with a vibrating tube densimeter. At all ternary solution compositions, one cross-term diffusion coefficient has negative values whereas the other has positive values. These measurements supplement our earlier results at 0.500 mol·dm-3. Both main-term diffusion coefficients are significantly smaller at 1.000 mol·dm-3 than at 0.500 mol·dm-3 at any fixed value of z 1, whereas both cross-term coefficients are shifted in a positive direction. Trace diffusion coefficients D*(Cl-) and D*(S ) were extrapolated from these results for the Cl-(aq) ion in 1.0 mol·dm-3 Na2SO4(aq) and for the S (aq) ion in 1.0 mol·dm-3 NaCl(aq). Values of D*(Cl-) in Na2SO4(aq) and in NaCl(aq) were found to be essentially identical, as were D*(S ) in these same two electrolytes, provided the comparisons were made at the same volumetric ionic strengths.

Measurements on densities, speeds of sound, viscosities, and relative permittivities for 21 binary mixtures of alkoxyethanols (2-methoxyethanol, 2-ethoxyethanol, and 2-butoxyethanol) + benzene, + toluene, + (o-, m-, and p-) xylenes, + ethylbenzene, and + cyclohexane at different temperatures are reported. The excess molar volumes, excess isentropic compressibilities, deviations in dynamic viscosities, speeds of sound, and relative permittivities have been calculated across the mole compositions. The compositional variation of excess and deviation functions has been expressed in terms of the Redlich-Kister equation.