Ammonium ferrocyanide

From Sciencemadness Wiki
Jump to: navigation, search
Ammonium ferrocyanide
Ammonium ferrocyanide sample.jpg
Ammonium ferrocyanide sample (the color is a lot stronger in person)
Names
IUPAC name
Ammonium hexacyanoferrate (II)
Other names
Ammonium hexacyanoferrate
Ammonium iron(II) hexacyanide
Tetraammonium hexacyanidoferrate
Tetraammonium hexacyanoferrate
Tetraazanium iron(II) hexacyanide
Properties
C6H16N10Fe
(NH4)4[Fe(CN)6] (anhydrous)
(NH4)4[Fe(CN)6]·xH2O (hydrated)
Molar mass 284.10 g/mol (anhydrous)
Appearance Lemon-green powdered solid
Odor Odorless
Melting point 95 °C (203 °F; 368 K) (decomposes)
Boiling point 95–290 °C (203–554 °F; 368–563 K) (decomposition range)
Soluble
Solubility Insoluble in alcohols
Vapor pressure ~0 mmHg
Hazards
Safety data sheet Acros Organics
Related compounds
Related compounds
Potassium ferrocyanide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Ammonium ferrocyanide or ammonium hexacyanoferrate (II) is an inorganic chemical compound with the chemical formula (NH4)4[Fe(CN)6]·xH2O. It is commonly available as hydrate.

Properties

Chemical

Thermal decomposition of ammonium ferrocyanide yields Prussian blue and finally iron(III) oxide. Cyanogen is produced during the decomposition. The decomposition occurs in several steps, and begins at 95 °C with the decomposition at 255-280 °C in air yielding ferric oxide.[1]

Heating the compound above 220 °C yields useful Prussian blue nanoparticles.

Physical

Ammonium ferrocyanide is a lemon-green powdered solid, odorless and soluble in water.

Availability

Ammonium ferrocyanide is sold by chemical suppliers.

Preparation

Ammonium ferrrocyanide can be prepared by mixing a solution of ammonium perchlorate with potassium ferrocyanide. The solution is cooled which precipitates out the poorly soluble potassium perchlorate, while ammonium ferrocyanide is recrystallized from the solution.

4 NH4ClO4 + K4[Fe(CN)6] → (NH4)4[Fe(CN)6] + 4 KClO4

Can also be prepared by neutralizing an aq. solution of ferrocyanic acid with aq. ammonia:

H4[Fe(CN)6] + 4 NH3→ (NH4)4[Fe(CN)6]

This route has the advantage of producing a very pure compound, free of any potassium impurities.[2]

Projects

Handling

Safety

Ammonium ferrocyanide (like all ferrocyanide complexes) is stable and practically nontoxic because of the strong bonding between iron and cyanide. The dry powder may be irritant if inhaled though.

Storage

In closed plastic or glass bottles, away from sunlight.

Disposal

No special disposal is required. Discard it as you wish.

References

  1. https://aip.scitation.org/doi/abs/10.1063/1.4966001
  2. HANDBOOK OF PREPARATIVE INORGANIC CHEMISTRY, G. Brauer, 1963, 2nd Ed.

Sciencemadness library

Relevant Sciencemadness threads