Trinitromethane, also referred to as nitroform, is a
nitroalkane
In organic chemistry, nitro compounds are organic compounds that contain one or more nitro functional groups (). The nitro group is one of the most common explosophores (functional group that makes a compound explosive) used globally. The nitr ...
and
oxidizer
An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or " accepts"/"receives" an electron from a (called the , , or ). In other words, an oxid ...
with chemical formula HC(NO
2)
3. It was first obtained in 1857 as the ammonium salt by the Russian chemist Leon Nikolaevich Shishkov (1830–1908). In 1900, it was discovered that nitroform can be produced by the reaction of
acetylene
Acetylene (systematic name: ethyne) is the chemical compound with the formula and structure . It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is unstable in its pure ...
with anhydrous
nitric acid
Nitric acid is the inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but older samples tend to be yellow cast due to decomposition into oxides of nitrogen. Most commercially available nitri ...
. This method went on to become the industrial process of choice during the 20th century. In the laboratory, nitroform can also be produced by hydrolysis of
tetranitromethane
Tetranitromethane or TNM is an organic oxidizer with chemical formula . Its chemical structure consists of four nitro groups attached to one carbon atom. In 1857 it was first synthesised by the reaction of sodium cyanoacetamide with nitric acid.
...
under mild basic conditions.
Acidity
Trinitromethane as a neutral molecule is colorless. It is highly acidic, easily forming an intensely yellow anion, (NO
2)
3C
−. The
p''K''a of trinitromethane has been measured at 0.17 ± 0.02 at 20 °C, which is remarkably acidic for a methane derivative. Trinitromethane easily dissolves in water to form an acidic yellow solution.
There is some evidence that the anion, which obeys the 4''n''+2
Hückel rule Hückel or Huckel may refer to:
* Erich Hückel (1896-1980), German physicist and chemist
** Debye–Hückel equation (named after Peter Debye and Erich Hückel), in chemistry, a method of calculating activity coefficients
** Hückel method (named ...
, is aromatic.
Nitroform salts
Trinitromethane forms a series of bright yellow ionic salts. Many of these salts tend to be unstable and can be easily detonated by heat or impact.
The potassium salt of nitroform, KC(NO
2)
3 is a lemon yellow crystalline solid that decomposes slowly at room temperatures and explodes above 95 °C. The ammonium salt is somewhat more stable, and deflagrates or explodes above 200 °C. The hydrazine salt,
hydrazinium nitroformate is thermally stable to above 125 °C and is being investigated as an ecologically friendly oxidizer for use in solid fuels for rockets.
References
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Nitroalkanes
Acids
Substances discovered in the 1900s