Diffusion Coefficients of Xylose and Maltose in Aqueous Solution

Diffusion coefficients for the systems aqueous xylose solution and aqueous malotse solution at 25°C were measured by the Rayleigh interference method. Viscosities of these systems were also determined. The concentration dependence of diffusion coefficient for maltose solution is well described by the Gordon relation. For xylose solution, however, a small deviation from this relation is observed. The translational frictional coefficient of maltose was calculated by the shell model of Bloomfield et al. If the effect of the local viscosity around a molecule of the solute is corrected, the agreement between the calculated and the observed values is satifsactory.