Tracer diffusivity of Ca45and electrical conductivity in CaO-SiO2 melts

The tracer diffusivity of Ca⁴⁵ has been measured in CaO-SiO₂ melts in the temperature range 1500 to 1700°C. In addition the electrical conductivity has been determined. Both properties decrease with increasing silica content. The activation energies (~30 kcal g-atom−1) are of the same order of magnitude. The electrical conductivity as computed from the diffusivity on the assumption that the total current is transported exclusively by divalent calcium ions and that the usual Nernst-Einstein relationship is valid, is somewhat lower than the measured electrical conductivity with the difference increasing with increasing silica content.