Preparation of potassium tetracyanonickelate(II) monohydrate
Six one-hundredths of a mole of any soluble nickel salt (16g of the sulfate, 14.5g chloride, or 17.5g nitrate —all 6-hydrate) is dissolved in 100ml of boiling water and a solution of 7g of pure potassium cyanide in 100ml water is slowly added dropwise with stirring. The liquid and its gray-green precipitate of hydrated nickel cyanide are digested for one hour on the steam bath (optional) to render the solid more easily filterable. The precipitate is collected on a Buchner funnel, washed with three 20ml portions of hot water, and pressed down well. The moist cake of residue and paper is transferred to a small dish and the filter paper is peeled clean from the solid, which is then re-moistened with about 10ml of water. On addition of a solution of 7g more of potassium cyanide in 15ml of water, the nickel cyanide dissolves with the formation of an orange-red solution. The clear liquid is evaporated to crystallization on the steam bath, cooled in ice, suction-filtered, and dried in air. Yield 12-13g.
Inorganic laboratory preparations, by G. G. Schlessinger, 95, 1962
Potassium tetracyanonickelate(II) hydrate, 339527-86-5, C4N4Ni.2K.H2O, 415154_ALDRICH, 7280AF, POTASSIUMTETRACYANONICKELATE HYDRATE
dipotassium nickel(2+) tetracyanide, 14323-41-2