Potassium ferrocyanide sample
K4[Fe(CN)6]•3H2O crystals, grown by following ChemPlayer's method of converting K3Fe(CN)6 to the ferrocyanide salt
| IUPAC name
| Other names
Ferrate hexacyano tetrapotassium trihydrate
Potassium hexacyanoferrate (II) trihydrate
Tetrapotassium ferrocyanide trihydrate
Yellow prussiate of potash
|Molar mass|| 368.35 g/mol (anhydrous)|
422.388 g/mol (trihydrate)
|Appearance||Light yellow solid|
|Density||1.85 g/cm3 (trihydrate)|
|Melting point||70 °C (158 °F; 343 K) (decomposes)|
| trihydrate |
28.9 g/100 ml (20 °C)
|Solubility||Insoluble in diethyl ether, ethanol, toluene|
|Safety data sheet||Sigma-Aldrich|
|Lethal dose or concentration (LD, LC):|
LD50 (Median dose)
|6400 mg/kg (oral, rat)|
| Prussian blue|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Potassium ferrocyanide or potassium hexacyanidoferrate(II) is is the potassium salt of the ferrocyanide coordination complex. It's generally available as trihydrate, K4[Fe(CN)6]·3 H2O.
Pyrolysis of potassium ferrocyanide will yield potassium cyanide:
- K4[Fe(CN)6] → 4 KCN + FeC2 + N2
Potassium ferrocyanide is a lemon yellow solid, soluble in water, but less so in organic solvents.
Potassium ferrocyanide can be purchased online.
Can be prepared by heating a nitrogen source, such as potassium nitrate, with iron and carbon.
Potassium ferrocyanide is irritant and should he handled with care.
While it contains cyanide groups, potassium ferrocyanide cannot be broken down to hydrogen cyanide in the organism, making it nontoxic.
In closed bottles, away from strong acidic vapors.
No special disposal is required. Can be dumped in trash.