Calcium Amide, Ca(NH₂)₂

When calcium ammonium is kept at ordinary temperatures, even in contact with ammonia, it slowly decomposes, giving transparent crystals of calcium amide, Ca(NH₂)₂.

By the action of hydrogen on calcium nitride at 300° C., Dafert and Miklauz obtained another amide to which they gave the formula Ca₃(NH₂)₂.

A number of substituted amides have been prepared by the action of organic amino-compounds on calcium, for example, calcium anilide, Ca(C₆H₅NH)₂, calcium ortho- and para-tolylamide, Ca(C₇H₇NH)₂, calcium diphenylamide, Ca(Cl₂H₁₀N)₂, and so on.

By the action of potassamide on a calcium salt in ammonia solution a white, amorphous, microcrystalline precipitate is obtained. It is insoluble in liquid ammonia but is dissolved and decomposed by a solution of ammonium nitrate in liquid ammonia, and is hydrolysed by water with the production of calcium hydroxide and ammonia. Franklin regarded it as CaNK.2NH₃, and called it potassium ammonocalciate. The formula might also be written as that of a molecular compound of the two amides Ca(NH₂)₂.KNH₂. If there is no excess of potassamide, calcium amide only is formed.