Potassium Ferricyanide laboratory grade manufacturer, supplier and exporter.
Potassium ferricyanide is also one of two compounds present in ferroxyl indicator solution (along with phenolphthalein) which turns blue (Prussian blue) in the presence of Fe2+ ions, and which can therefore be used to detect metal oxidation that will lead to rust. It is possible to calculate the number of moles of Fe2+ ions by using a colorimeter, because of the very intense color of Prussian blue Fe4[Fe(CN)6]3.
Potassium ferricyanide has very low toxicity, its main hazard being that it is a mild irritant to the eyes and skin. However, under very strongly acidic conditions, highly toxic hydrogen cyanide gas is evolved, according to the equation:
6 H+ + [Fe(CN)6]3− → 6 HCN + Fe3+
The reaction with hydrochloric acid is as follows:
6 HCl + K3[Fe(CN)6] → 6 HCN + FeCl3 + 3 KCl
IUPAC name : Potassium Hexacyanidoferrate(II)
CAS number 13943-58-3
RTECS number LJ8225000
Molecular formula C6N6FeK4
Molar mass 368.35 g/mol
Appearance deep red crystals
Density 1.85 g/cm3, solid
Melting point 300 °C, 573 K, 572 °F
Boiling point : decomp.
Solubility in water 330 g/L ("cold water")
464 g/L (20°C)
775 g/L ("hot water")
Solubility slightly soluble in alcohol
soluble in acid
soluble in water
|Physical state and appearance||Solid. (crystalline powder.)|
|Molecular Weight||329.25 g/mole|
|pH (1% soln/water)||Not available|
|Boiling Point||Not available|
|Critical Temperature||Not available|
|Specific Gravity||1.85 (Water = 1)|
|Vapor Pressure||Not applicable|
|Vapor Density||Not available|
|Odor Threshold||Not available|
|Water/Oil Dist. Coeff||Not available|
|Ionicity (in Water)||Not available|
|Dispersion Properties||See solubility in water|
|Solubility||Soluble in cold water|
|Stability||The product is stable|
|Instability Temperature||Not available|
|Conditions of Instability||Heat, light, incompatible materials|
|Incompatibility with various substances||Reactive with acids|
|Corrosivity||Non-corrosive in presence of glass|
The potassium and sodium ferrocyanides are also used in the purification of tin and the separation of copper from molybdenum ores. Potassium ferrocyanide is used in the production of wine and citric acid.
It can also be used in animal feed.
In the laboratory, potassium ferrocyanide is used to determine the concentration of potassium permanganate, a compound often used in titrations based on redox reactions.
Thus it is used as an identifying reagent for iron in labs.
Detecting free Iron : Spray the surface with a solution of potassium ferricyanide. If free iron is present, a blue color will appear. This test is extremely sensitive and often gives false positive results, that is, it gives an indication of iron being present when it really is not. The ferroxyl solution must be made fresh each day by addition with Nitric acid. The ferroxyl tests are described in ASTM A380.