Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

The densities of {water (1) + tert-butanol (2)} binary mixture were measured over the temperature range (274.15 to 348.15) K at atmospheric pressure using Anton Paar digital vibrating-tube densimeter. Density measurements were carried out over the whole concentration range at (308.15 to 348.15) K. The following volume parameters were calculated: excess molar volumes and thermal isobaric expansivities of the mixture, partial molar volumes and partial molar thermal isobaric expansivities of the components. Concentration dependences of excess molar volumes were fitted with Redlich-Kister equation. The results of partial molar volume calculations using four equations were compared. It was established that for low alcohol concentrations at T less than 208 K the inflection points at near x2 = 0.02 were observed at concentration dependences of specific volume. The concentration dependences of partial molar volumes of both water and tert-butanol had extremes at low alcohol content. The temperature dependence of partial molar volumes of water had some inversion at near x2 = 0.65. The temperature dependence of partial molar volumes of tert-butanol at infinite dilution had minimum at near 288 K. It was discovered that concentration dependences of thermal isobaric expansivities of the mixture at small alcohol content and low temperatures passed through minimum.