Thermodynamics Research Center / ThermoML | Thermochimica Acta

ABSTRACT

The density of {water (1) + ethylenediamine (2)} binary mixture was measured over the whole concen-tration range at temperatures from 274.15 to 333.15 K and at atmospheric pressure. The experimentalvalues were used to calculate a whole number of the mixture parameters such as the excess molarvolumes, molar isobaric expansions, apparent and partial molar volumes, partial molar isobaric expan-sions, limiting partial molar volumes and limiting partial molar isobaric expansions both of water andethylenediamine. The extremal dependence of the partial molar volumes of the mixture components wasobserved; the mixture excess molar volumes were negative at all temperatures and depended weakly ontemperature. The concentration dependences of the partial molar volumes of the mixture componentswere very similar to the dependences for aqueous mixtures of the nonelectrolytes with hydrophobicproperties. The mixture molar isobaric expansion increased with ethylenediamine concentration overthe whole concentration range. The concentration dependences of partial molar isobaric expansions ofboth water and ethylenediamine were rather complex and correlated with the mixture melting diagram.