5533. Lithium Hydride

Nomenclature

CAS number: 7580-67-8
HLi; mol wt 7.95.
H 12.68%, Li 87.31%.
LiH.

Description and references

Prepd by the direct combination of hydrogen and lithium: Gibb, Trans. Electrochem. Soc. 93, 198-211 (1948). Review of prepn and properties: Truter in Mellor's vol. II, supplement II, The Alkali Metals (part 1) 131-145 (1961).

Properties

Cubic crystals, darkens rapidly on exposure to light, the commercial product is usually gray. mp 680°. d 0.76-0.77. Dangerous when wet. No solvent known. Rapidly dec in water to form lithium hydroxide and hydrogen. Reacts with the lower alcohols, carboxylic acids, chlorine, and ammonia at 400° to liberate hydrogen.

Caution

Potential symptoms of overexposure are irritation and burns of eyes and skin; burns of mouth and esophagus (if ingested); nausea; muscle twitches; mental confusion; blurred vision. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 186.

Use

Reducing agent; condensing agent with ketones and acid esters; desiccant; in hydrogen generators; 1 g in water liberates ≈2.8 liters of hydrogen at STP.