Trisodium hexakiscyanoferrate

Tetrasodium hexakiscyanoferrate decahydrate [14434-22-1], Na4[Fe(CN)g] IOH2O, or yellow pmssiate of soda, forms yellow monoclinic crystals that are soluble in water but insoluble in alcohol. It is slightly efflorescent at room temperature, but the anhydrous material, tetrasodium hexakiscyanoferrate [13601 -19-9], Na4[Fe(CN)J, is obtained at 100°C. The decahydrate is produced from calcium cyanide, iron(II) sulfate, and sodium carbonate in a process similar to that for the production of K4[Fe(CN)g] 3H2O. It is used in the manufacture of trisodium hexakiscyanoferrate, black and blue dyes, as a metal surface coating, and in photographic processing. 

Trisodium hexakiscyanoferrate [14217-21-17, Na2[Fe(CN) J, forms red hygroscopic crystals that are soluble in water. A monohydrate [13755-37-8] and a dihydrate [36249-31-7] are also known. The sodium salt is used for many of the same purposes as the potassium salt. 

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