SOLUTIONS OF SALTS IN LIQUID-SODIUM ELECTRICAL-RESISTIVITY OF SOLUTIONS OF SODIUM HYDRIDE AND OF SODIUM MONOXIDE, AND SOLUBILITY OF SODIUM HYDRIDE IN SODIUM

The electrical resistivity of solutions of sodium hydride (between 340 and 430 °C) and of sodium monoxide (at 400 °C) in liquid sodium up to saturation concentrations has been determined. The resistivity increases linearly with increasing concentration of each salt but hydride ions scatter conduction electrons more effectively; unit resistivity increases are 4.5 × 10-8 and 1.8 × 10-8 Ω m (mol.%)-1 for H- and O2-, respectively, which may reflect the difference in size of the solvated anions. The solubility of sodium hydride was determined from the change in resistivity which occurred on saturation. Values are combined with those derived from pressurecomposition isotherms to give the solubility equation: Iog10 (mol.% H) = 4.82 - 3600/T 613 ≤ T ≤ 673 K. © 1978.