Volumetric properties of the water-ethylene glycol mixtures in the temperature range 278–333.15 K at atmospheric pressure

Abstract

Density of the water-ethylene glycol binary mixtures was measured in the entire range of compositions in the temperature range 278–333.15 K (6 values) at atmospheric pressure using a vibration densimeter. Mixtures with low concentrations of ethylene glycol were studied at 15 temperatures in the range of 274–333.15 K. Excess molar volumes VmE, the partial molar volumes of water -V1 and ethylene glycol, -V2, the coefficients of thermal volume expansion α of the mixture, the partial molar volume coefficients of thermal expansion of water \( \bar V_1 \) and ethylene \( \bar V_2 \) were calculated. Excess molar volumes were described using the Redlich-Kister equation. The density ρ of the mixture was found to increase with the increasing ethylene glycol concentration at all temperatures, but at low content of ethylene glycol the dependence ρ = f(T) of the mixture at ∼276.5 K passed through a maximum. The coefficient α increases sharply in the composition range 0 277 K is positive for all compositions. The dependences \( \bar \alpha _1 \) = f (x) and \( \bar \alpha _2 \) = f (x) are complex in whole temperature range and are characterized by the presence of an extremum. VmE values are negative at all temperatures, and upon increase in the temperature the deviation from ideality decreases (x is the mole fraction of ethylene glycol).