Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

Densities and ultrasonic speed of ethylene glycol, diethylene glycol and triethylene glycol in (0.00, 0.01, 0.03, 0.05) mol kg-1 aqueous solutions of glycerol have been measured at T = (293.15, 298.15, 303.15, 308.15) K and experimental pressure p = 0.1 MPa. From the density data, the apparent molar volume Vphi, the partial molar volume Vphio and the partial molar volumes of transfer deltaVphio have been calculated for glycols from water to aqueous glycerol solutions. Using ultrasonic speed values apparent molar isentropic compression Kphi,s, partial molar isentropic compression Kphi,so and partial molar isentropic compression of transfer deltaKphi,so, have been evaluated. The pair and triplet coefficients have been computed from partial molar volumes of transfer and partial molar isentropic compression of transfer. The apparent molar isobaric expansion at infinite dilution (dVphi0/dT)p, second order derivative (d2Vphi0/dT2)p have also been calculated. The parameters thus obtained have been discussed in terms of (solute-solute)/(solute-solvent) interactions prevailing in the present ternary system along with structure making/structure breaking tendency of glycols in aqueous glycerol solutions.