Aluminium nitride (A1N) is obtained as small yellow crystals when aluminium is strongly heated in nitrogen.
Boron nitride BN is formed when boron is burned either in air or in nitrogen, but can be obtained more readily by heating to redness in a platinum crucible a mixture of one part of anhydrous borax with two parts of dry ammonium chloride.
After fusion, the melt is well washed with dilute hydrochloric acid and then with water, the nitride remaining as a white powder.
Borimide B 2 (NH) 3 is obtained on long heating of the compound B 2 S 3.6NH 3 in a stream of hydrogen, or ammonia gas at 115-120° C. It is a white solid which decomposes on heating into boron nitride and ammonia.
P. 862), calcium is heated in a current of hydrogen, and nitrogen passed over the hydride so formed; this gives ammonia and calcium nitride, the latter of which gives up its nitrogen as ammonia and reforms the hydride when heated in a current of hydrogen.