Nickel(II) cyanide
Nickel cyanide is the inorganic compound with a chemical formula Ni2. The trihydrate is a gray-green solid that is insoluble in most solvents including water, while the anhydrous form is a yellow solid.
Production
Addition of two equivalents of sodium or potassium cyanide to a solution of nickel ions in aqueous solution leads to the precipitation of nickel cyanide trihydrate. On heating the trihydrate to 140 °C, this hydrate converts to anhydrous nickel cyanide.Chemical properties
Nickel cyanide dissolves in potassium cyanide solution to produce a yellowish solution containing potassium tetracyanonickelate:Nickel cyanide will react with dimethylglyoxime and produce hydrogen cyanide: