8625. Sodium Hydride

Nomenclature

CAS number: 7646-69-7
HNa; mol wt 24.00.
H 4.20%, Na 95.79%.
NaH.

Description and references

Prepd by passing hydrogen into molten sodium dispersed in oil or mixed with a catalyst such as anthracene above 250°: Hansley, Carlisle, Chem. Eng. News 23, 1332 (1945). Laboratory procedure by hydrogenating sodium dispersions: Mattson, Whaley, Inorg. Synth. 5, 10 (1957). Book: J. Plesek, S. Hermanek, Sodium Hydride, Its Use in the Laboratory and in Technology (Iliffe Books, London, 1968) 185 pp.

Properties

Silvery needles; the commercial product is a gray-white powder. d 1.396. Dec 425°. Dangerous when wet. Reacts explosively with water, violently with lower alcohols, ignites spontaneously on standing in moist air. Sol in molten sodium hydroxide, insol in liquid ammonia but forms sodamide at moderate temps.

Use

At low temps where reducing properties of sodium are undesirable as in the condensation of ketones and aldehydes with acid esters; in soln with molten sodium hydroxide for the reduction of oxide scale on metals; at high temps as a reducing agent and reduction catalyst.