Ammonium cyanide

Ammonium cyanide

Identifiers
CAS Number	12211-52-8 Y
3D model (JSmol)	Interactive image
ChemSpider	140210 Y
PubChem CID	159440
UNII	898Y75UR3N Y
CompTox Dashboard (EPA)	DTXSID00153500
InChI InChI=1S/CN.H3N/c1-2;/h;1H3/q-1;/p+1 Y Key: ICAIHGOJRDCMHE-UHFFFAOYSA-O Y InChI=1/CN.H3N/c1-2;/h;1H3/q-1;/p+1 Key: ICAIHGOJRDCMHE-IKLDFBCSAW
SMILES [C-]#N.[NH4+]
Properties
Chemical formula	NH4CN
Molar mass	44.0559 g/mol
Appearance	colourless crystalline solid
Density	1.02 g/cm3
Boiling point	36 °C (97 °F; 309 K)
Solubility in water	very soluble
Solubility	very soluble in alcohol
Structure
Crystal structure	cubic
Related compounds
Other anions	Ammonium hydroxide Ammonium azide Ammonium nitrate
Other cations	Sodium cyanide Potassium cyanide
Related compounds	Ammonia Hydrogen cyanide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Ammonium cyanide is an unstable inorganic compound with the formula NH₄CN.

Uses

Ammonium cyanide is generally used in organic synthesis. Being unstable, it is not shipped or sold commercially.

Preparation

Ammonium cyanide is prepared in solution by bubbling hydrogen cyanide into aqueous ammonia at a low temperature

HCN + NH₃ (aq) → NH₄CN (aq)

It may be prepared by the reaction of calcium cyanide and ammonium carbonate:

Ca(CN)₂ + (NH₄)₂CO₃ → 2 NH₄CN + CaCO₃

In dry state, ammonium cyanide is made by heating a mixture of potassium cyanide or potassium ferrocyanide with ammonium chloride and condensing the vapours into ammonium cyanide crystals:

KCN + NH₄Cl → NH₄CN + KCl

Reactions

Ammonium cyanide decomposes to ammonia and hydrogen cyanide, often forming a black polymer of hydrogen cyanide:^[1]

NH₄CN → NH₃ + HCN

It undergoes salt metathesis reaction in solution with a number of metal salts to form metal–cyanide complexes.

Reaction with ketones and aldehydes yield aminonitriles, as in the first step of the Strecker amino acid synthesis:

NH₄CN + CH₃COCH₃ → (CH₃)₂C(NH₂)CN + H₂O

Toxicity

The solid or its solution is highly toxic. Ingestion can cause death. Exposure to the solid can be harmful as it decomposes to highly toxic hydrogen cyanide and ammonia.

Chemical analysis

Ammonium cyanide may be analyzed by heating the salt and trapping the decomposed products: hydrogen cyanide and ammonia in water at low temperatures. The aqueous solution is analyzed for cyanide ion by silver nitrate titrimetric method or an ion-selective electrode method, and ammonia is measured by titration or electrode technique.

Notes

References

• A. F. Wells, Structural Inorganic Chemistry, 5th ed., Oxford University Press, Oxford, UK, 1984.

This page was last edited on 25 January 2022, at 18:33