Ammonium formate

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Ammonium formate
Ammonium formate wet by NileRed.jpg
Wet ammonium formate
Names
IUPAC name
Ammonium formate
Other names
Azanium formate
Identifiers
Jmol-3D images Image
Properties
CH5NO2
NH4HCOO
Molar mass 63.06 g/mol
Appearance White hygroscopic solid
Odor Slightly ammoniac
Density 1.26 g/cm3
Melting point 116 °C (241 °F; 389 K)
Boiling point 180 °C (356 °F; 453 K) (decomposes)
102 g / 100 ml (0 °C)
142.7 g / 100 ml (20 °C)
202.4 g / 100 ml (40 °C)
516 g / 100 ml (80 °C)
Solubility Soluble in liquid ammonia, diethyl ether, ethanol, methanol
Insoluble in acetone, benzene, chloroform, toluene
Thermochemistry
−556.18 kJ/mol
Hazards
Safety data sheet ScienceLab
Lethal dose or concentration (LD, LC):
410 mg/kg (mice, intravenous)
Related compounds
Related compounds
Ammonium acetate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Ammonium formate is an organic chemical compound, an ammonium salt of formic acid. It is a colorless, hygroscopic solid, with the chemical formula NH4HCOO.

Properties

Chemical

Heating ammonium formate will cause it to convert it into formamide:

NH4HCO2 → HCONH2 + H2O

Further heating the formamide will cause it to decompose into carbon monoxide and ammonia, while at higher temperatures and in the presence of an acid catalyst will yield hydrogen cyanide:

HC(O)NH2 → CO + NH3
HC(O)NH2 → HCN + H2O

Ammonium formate can be used in the reductive amination of aldehydes and ketones, process known as Leuckart reaction.

One example is the conversion of acetone to isopropylamine:

HCOONH4 + (CH3)2CO → (CH3)2HC-NH2 + H2O + CO2

Physical

Ammonium formate is a hygroscopic white crystalline solid, soluble in water.

If wet ammonium formate is left to dry in a desiccator over the course of weeks or months, tiny white crystals of dry ammonium formate shaped like snowflake arms or fern leaves will form on the edge of the flask.

Availability

Ammonium formate is sold by big chemical suppliers, while smaller suppliers rarely have it in their stock.

Preparation

Ammonium formate can be made by bubbling ammonia through formic acid, though this requires lots of ammonia. An ammonium salt, such as ammonium bicarbonate can be used instead. Cooling the solution will cause the salt to precipitate. Excess water can be evaporated by carefully heating the solution, at below 115 °C, to prevent it from melting/decomposing. Filter the resulting precipitate and leave it to dry, either in open air or in a desiccator. Heating will not dry ammonium formate, instead it will decompose, resulting in a yellow syrup containing water, formamide and ammonium formate.[1]

Since it's hygroscopic, it's best to keep it in a desiccator until you need it.

Projects

Handling

Safety

Ammonium formate may release formic acid vapors and protection should be worn when handling the compound.

Storage

Ammonium formate should be kept in closed bottles, away from moisture. Can be stored in a desiccator. Ammonia may be added to limit hydrolysis.

Disposal

Mixing it with an alkali will neutralize it, though it's best to do this outside, as the reaction gives off ammonia.

References

  1. https://www.youtube.com/watch?v=CuiLFCaYseo

Relevant Sciencemadness threads