Electrical conductance in binary molten nitrate mixtures. 2

Abstract

Presently at the Department of Chemistry, Hindu College, Delhi 110007, India. 100-150 OC under vacuum for several days. Calcium and cadmium nitrate tetrahydrates were first dried by slow and careful heating under vacuum below 85 O C for 3-4 days and then at 150-200 O C for 12 h. Sample compositions, checked by EDTA titrations, were within the experimental uncertainty, to the intended compositions. Dehydrated samples were stored over anhydrous magnesium perchlorate until used. All manipulations, e.g., preparing the mixtures, loading the conductivity cell, etc., were done in a drybox under a flowing nitrogen atmosphere, the gas having been dried by passing through anhydrous silica gel and magnesium perchlorate columns. The capillary type cells were used. The cell constants (ranging between 120 and 350 cm-') were determined using 1 N KCI and saturated sodium chloride solutions at 18.0 f 0.02 O C , employing platinized platinum electrodes of ca. 1 cm2 area. No significant change in the value of cell constants was observed even after five-six runs; in practice, cells were discarded after this much use. About 50 g of the mixture was taken in one of the limbs of the conductivity cell, held in an electric furnace of high thermal inertia, and fused in situ under a stream of nitrogen. The melt was maturedby keeping at a temperature 10-15