THERMODYNAMICS OF AQUEOUS MIXTURES OF 2-(2-HEXYLOXYETHOXY)ETHANOL AT 5-DEGREES-C

The densities and the ultrasonic speeds of the aqueous solutions of 2- (2-hexyloxyethoxy)ethanol (C(6)E(2)) were measured over the entire ran ge of mole fractions at 5 degrees C. Excess molar volumes V-E Were rea dily calculated front the densities. The densities, in combination wit h the ultrasonic speeds, furnish estimates of the molar (and excess mo lar) isentropic compressibilities K-S and the deviations u(D) ofthe ul trasonic speeds from the values calculated for ideal mixtures. Radical changes in the mole fraction derivatives ofthe excess molar propertie s of the (C(6)E(2) + water) system, in the vicinity of an amphiphile m ole fraction of 0.003, indicate that C(6)E(2) like C(6)E(3) is capable of micelle formation. Our data have been compared with those reported earlier for (C(4)E(2) +, C(2)E(2) +, and C(6)E(3) + water). We have e mployed both mass action and pseudophase approaches to data analysis, together with the four-segment model approach.