Volumetric Properties of Urea in the Mixture of N,N-Dimethylformamide with Water

The density of urea (U) in the mixtures of N,N-dimethylformamide (DMF) and water (H2O) was measured within the temperature range of (293.15 to 308.15) K. The results obtained were used to calculate the excess molar volume, V-E, of the DMF-H2O mixture, apparent molar volumes, V-Phi, of DMF in water and of water in DMF, as well as the partial molar volume of urea in a solution at infinite dilution, V-m(infinity), within the whole concentration range of the mixed solvent (DMF-H2O). The data obtained were discussed from the point of view of temperature changes and interaction in solution.