Lithium Arsenates

Lithium Orthoarsenate is obtained as the hemihydrate, 2Li₃AsO₄.H₂O, by the action of lithium carbonate on arsenic acid and allowing the solution to crystallise. The anhydrous salt is prepared by recrystallising this hydrate from fused lithium chloride; rhombic crystals of density 3.07 at 15° C. are obtained. These are soluble in dilute acetic acid; they are extremely stable and may be heated to a white heat without fusion. With excess of arsenic acid the normal salt yields deliquescent rhombic prisms of lithium dihydrogen arsenate, 2LiH₂AsO₄.3H₂O, which with water revert to the normal salt.