Taylor dispersion equipment installed at the University of Coimbra for the measurement of diffusion in liquids has been tested to ensure adequate accuracy and precision by measuring mutual diffusion coefficients for binary aqueous solutions of sucrose, glycine, lithium chloride, potassium chloride, and hydrochloric acid at 298.15 K. In addition, binary mutual diffusion coefficients for aqueous solutions of lactic acid (not previously reported in the literature) have been measured at 298.15 and 303.15 K and concentrations up to 0.20 mol-dm −3 .

No abstract

No abstract

No abstract

No abstract

No abstract

a b s t r a c tExperimental values for mutual diffusion coefficients (interdiffusion coefficients) for CaCl 2 aqueous solutions at 298.15 K and 310.15 K, not available in the literature, were experimentally determined between 0.005 mol dm −3 and 0.1 mol dm −3 . The measurements were performed by using a conductimetric openended capillary cell. Values at infinitesimal concentration, D 0 , were also obtained. These data were analysed using the Onsager-Fuoss and Gordon models. In addition, molar conductance data were measured at 310.15 K for CaCl 2 aqueous solutions at the same concentration range and the value at infinitesimal concentration determined. Afterwards, it was split into the ionic limiting values. By replacing them into the Nernst equation, diffusion coefficients at infinitesimal concentration were derived (1.335 × 10 −9 m 2 s −1 and 1.659 × 10 −9 m 2 s −1 ) at both temperatures (298.15 K and 310.15 K, respectively). They agree well with the extrapolated experimental ones (1.312 × 10 −9 m 2 s −1 and 1.613 × 10 −9 m 2 s −1 ).

No abstract