Diffusion coefficients of alkyl ureas in aqueous solution at 25°C

The free diffusion coefficients of aqueous solutions of methyl-, 1,3-dimethyl-, ethyl-, and 1,3-diethylurea have been measured at 25°C by the Gouy interferometric technique. With the help of literature activity data the thermodynamic diffusion and the frictional coefficients are computed and a qualitative discussion of their concentration dependence is attempted.