Calcium nitride is a red-brown, crystalline solid made up of calcium and nitrogen. Its chemical formula is Ca3N2. α-Calcium nitride is the commonly encountered form. It has an anti-bixbyite structure similar to Mn2O3, except that the positions of the ions are reversed: calcium (Ca2+) take the oxide (O2−) positions and nitride ions (N3−) the manganese (Mn3+).
Calcium nitride is formed along with the oxide, CaO, when calcium burns in air. It can be produced by direct reaction of the elements:
- 3 Ca + N2 → Ca3N2
It reacts with moisture in air to give ammonia and calcium hydroxide:
- Ca3N2 + 6 H2O → 3 Ca(OH)2 + 2 NH3
This reaction also occurs in water.
It absorbs hydrogen above 350 °C:
- Ca3N2 + 2 H2 → 2 CaNH + CaH2
Read more about Calcium Nitride: General References