Liquid ammonia is an excellent solvent for a large number of different types of substances (1). Although it does not surpass water as a solvent for most inorganic substances, it appears to excel as a medium for organic compounds; in this it resembles alcohol. It exhibits a distinct advantage over water in that it dissolves the alkali and alkaline earth metals without appreciable reaction with them. The fact that reaction does not proceed is undoubtedly due to the extremely low concentration of the amide ions present in liquid ammonia. This condition is substantiated by the low conductivity of pure ammonia and also by the small tendency for ammonolytic reactions to proceed as compared to hydrolytic reactions in water. Substances which are readily hydrolyzed in water are, as a rule, not ammonolyzed in liquid ammonia. Thus it is possible to study the chemical and physical properties of the strongly electropositive elements in a comparatively inert medium possessing a high dielectric constant. In the present discussion we shall confine ourselves to the physical properties of these solutions and shall attempt to give a critical account of the results of the numerous investigations.
SOLUBILITY RELATIONSSolutions of the alkali metals in liquid ammonia were first investigated by Weyl in 1864 (2). He observed that sodium and potassium were soluble in this medium, producing highly colored solutions. At the time of his studies the radical theory domi-
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.