Barium cyanide is a chemical compound with the formula Ba(CN)<sub>2</sub>. It is synthesized by the reaction of hydrogen cyanide and barium hydroxide in water or petroleum ether. It is a white crystalline salt.
Barium cyanide is used in electroplating and other metallurgical processes.
Barium cyanide is prepared by reacting barium hydroxide with hydrocyanic acid:
The product is crystallized from the solution.
Barium cyanide reacts with water and carbon dioxide in air slowly, producing highly toxic hydrogen cyanide gas.
When barium cyanide is heated to 300ðC with steam present, the nitrogen evolves to ammonia, leaving barium formate.
Aqueous solutions of barium cyanide dissolve insoluble cyanides of some of the heavy metals forming crystalline double salts. For example, BaHg(CN)<sub>4</sub>.3H<sub>2</sub>O in needles, 2Ba(CN)<sub>2</sub>.3Hg(CN)<sub>2</sub>.23H<sub>2</sub>O in transparent octahedra, and Ba(CN)<sub>2</sub>.Hg(CN)<sub>2</sub>.HgI<sub>2</sub>.6H<sub>2</sub>O.