Viscosity of Urea in the Mixture of <i>N</i>,<i>N</i>-Dimethylformamide and Water

Abstract

The viscosity of urea (U) in the mixtures of N,N-dimethylformamide (DMF) and water (H2O) was measured within the temperature range from (293.15 to 308.15) K. The results obtained were used to calculate the dynamic viscosities, η, of the DMF–H2O mixture and urea in aqueous DMF solution. Based on the relative viscosity values calculated, ηr, and Jones–Dole’s equation, the values and sign of viscosity coefficient B were determined and analyzed on account of the destructive or constructive properties of urea regarding the solvent structure. The data obtained were discussed from the point of view of temperature changes and interactions in solutions.