Fulminate

Fulminates are chemical compounds which include the fulminate ion. The fulminate ion is a pseudohalic ion, acting like a halogen with its charge and reactivity. Due to the instability of the ion, they are friction-sensitive explosives. The best known is mercury fulminate which has been used as a primary explosive in detonators. Fulminates can be formed from metals, like silver and mercury, dissolved in nitric acid and reacted with alcohol. The chemical formula for the fulminate ion is O⁻N⁺C⁻. It is largely the presence of the weak single nitrogen-oxygen bond which leads to its instability. Nitrogen very easily forms a stable triple bond to another nitrogen atom, forming gaseous nitrogen.

Historical notes

Fulminates were discovered by Edward Charles Howard in 1800.^[1][2][3]. Their use in firearms in a fulminating powder was first demonstrated by a Scottish minister, A. J. Forsyth, who was granted a patent in 1807^[4]. Joshua Shaw then made the transition to their use in metallic encapsulations, to form a percussion cap, but did not patent his invention until 1822.

In the 1820s, the organic chemist Justus Liebig discovered silver fulminate (Ag-CNO) and Friedrich Wöhler discovered silver cyanate (Ag-NCO). The fact that these substances have the same chemical composition led to an acrid dispute, which was not resolved until Jöns Jakob Berzelius came up with the concept of isomers^[5].

Compounds

• Silver fulminate
• Mercury(II) fulminate
• Fulminic acid
• Cyanate, has related OCN⁻ structure

References

1. ^ Edward Howard (1800). "On a New Fulminating Mercury.". Philosophical Transactions of the Royal Society of London 90 (1): 204-238.
2. ^ F. Kurzer (1999). "The Life and Work of Edward Charles Howard". Annals of Science 56: 113-141. doi:10.1080/000337999296445.
3. ^ Edward Charles Howard (1774-1816), Scientist and sugar refiner publisher = National Portrain Gallery (January 5, 2005). Retrieved on 2006-08-30.
4. ^ Rifled Breach Loader. Globalsecurity.org.
5. ^ Greenberg, Arthur (2000). A Chemical History Tour. John Wiley & Sons, 198-203. ISBN 0-471-35408-2. 

See also

• percussion cap
• internal ballistics