Volumetric properties of the water + tetramethylurea mixture over the temperature range from 274.15 to 333.15 K at atmospheric pressure

Abstract

The densities of the binary mixture {water (1) + tetramethylurea (2)} have been measured in the entire composition range in the temperature range from 274.15 K to 333.15 K at atmosphere pressure. Excess molar volumes and molar isobaric thermal expansions of the mixture, apparent and partial molar volumes, partial molar isobaric expansions of water and tetramethylurea (TMU), including their limiting values, are calculated. It is shown that the formation of the water + tetramethylurea mixture occurs with a decrease in the volume of the mixture at all temperatures, and the partial molar volumes of water and TMU increase with increasing temperature. The temperature dependences of the limiting partial molar isobaric thermal expansions of both components are characterized by the presence of the extremum. The obtained results are discussed in terms of solute-solvent and solute-solute interactions.