Fulminates are

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

s which include the fulminate ion (). The fulminate ion is a

pseudohalic Pseudohalogens are polyatomic analogues of halogens, whose chemistry, resembling that of the true halogens, allows them to substitute for halogens in several classes of chemical compounds. Pseudohalogens occur in pseudohalogen molecules, inorganic ...

ion because its charge and reactivity are similar to those of the

halogen The halogens () are a group in the periodic table consisting of five or six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and tennessine (Ts). In the modern IUPAC nomenclature, this grou ...

s. Due to the instability of the ion, fulminate

salts In chemistry, a salt is a chemical compound consisting of an ionic assembly of positively charged cations and negatively charged anions, which results in a compound with no net electric charge. A common example is table salt, with positively c ...

are friction-sensitive

explosive An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An expl ...

s. The best known is

mercury(II) fulminate Mercury(II) fulminate, or Hg(CNO)2, is a primary explosive. It is highly sensitive to friction, heat and shock and is mainly used as a trigger for other explosives in percussion caps and detonators. Mercury(II) cyanate, though its chemical formul ...

, which has been used as a

primary explosive An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An ...

detonator A detonator, frequently a blasting cap, is a device used to trigger an explosive device. Detonators can be chemically, mechanically, or electrically initiated, the last two being the most common. The commercial use of explosives uses electr ...

s. Fulminates can be formed from metals, such as

silver Silver is a chemical element with the symbol Ag (from the Latin ', derived from the Proto-Indo-European ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical ...

and mercury, dissolved in nitric acid and reacted with

ethanol Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a ...

. The weak single nitrogen-oxygen bond is responsible for their instability. Nitrogen very easily forms a stable

triple bond A triple bond in chemistry is a chemical bond between two atoms involving six bonding electrons instead of the usual two in a covalent single bond. Triple bonds are stronger than the equivalent single bonds or double bonds, with a bond order o ...

to another nitrogen atom, forming nitrogen gas.

Historical notes

Fulminates were discovered by Edward Charles Howard in 1800. The use of fulminates for firearms was first demonstrated by a Scottish minister,

Alexander John Forsyth Alexander John Forsyth (28 December 1768 – 11 June 1843) was a Scottish Church of Scotland minister who first successfully used fulminating (or 'detonating') chemicals to prime gunpowder in fire-arms thereby creating what became known as pe ...

, who patented his scent-bottle lock in 1807; this was a small container filled with

fulminate of mercury Mercury(II) fulminate, or Hg(CNO)2, is a primary explosive. It is highly sensitive to friction, heat and shock and is mainly used as a trigger for other explosives in percussion caps and detonators. Mercury(II) cyanate, though its chemical formula ...

. Joshua Shaw determined how to encapsulate them in metal to form a

percussion cap The percussion cap or percussion primer, introduced in the early 1820s, is a type of single-use percussion ignition device for muzzle loader firearm locks enabling them to fire reliably in any weather condition. This crucial invention gave rise ...

, but did not patent his invention until 1822. In the 1820s, the organic chemist

Justus Liebig Justus Freiherr von Liebig (12 May 1803 – 20 April 1873) was a German scientist who made major contributions to agricultural and biological chemistry, and is considered one of the principal founders of organic chemistry. As a professor at the ...

discovered

silver fulminate Silver fulminate (AgCNO) is the highly explosive silver salt of fulminic acid. Silver fulminate is a primary explosive, but has limited use as such due to its extreme sensitivity to impact, heat, pressure, and electricity. The compound becomes ...

(AgCNO) and

Friedrich Wöhler Friedrich Wöhler () FRS(For) Hon FRSE (31 July 180023 September 1882) was a German chemist known for his work in inorganic chemistry, being the first to isolate the chemical elements beryllium and yttrium in pure metallic form. He was the fi ...

discovered silver cyanate (AgOCN). They have different properties but the same

chemical composition A chemical composition specifies the identity, arrangement, and ratio of the elements making up a compound. Chemical formulas can be used to describe the relative amounts of elements present in a compound. For example, the chemical formula for ...

, which led to a bitter dispute finally resolved by Jöns Jakob Berzelius through the concept of

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Is ...

Compounds

Fulminic acid Fulminic acid is an acid with the formula HCNO, more specifically . It is an isomer of isocyanic acid () and of its elusive tautomer, cyanic acid (), and also of isofulminic acid (). Fulminate is the anion or any of its salts. For historic ...

Mercury(II) fulminate Mercury(II) fulminate, or Hg(CNO)2, is a primary explosive. It is highly sensitive to friction, heat and shock and is mainly used as a trigger for other explosives in percussion caps and detonators. Mercury(II) cyanate, though its chemical formul ...

Potassium fulminate Potassium fulminate is the potassium salt of the fulminate ion. Its only use, aside from chemical demonstrations, is in the percussion caps for some early rifles. Usually prepared by reacting a potassium amalgam with mercury fulminate, it is mu ...

Silver fulminate Silver fulminate (AgCNO) is the highly explosive silver salt of fulminic acid. Silver fulminate is a primary explosive, but has limited use as such due to its extreme sensitivity to impact, heat, pressure, and electricity. The compound becomes ...

References

{{carbon compounds Oxyanions

Historical notes

Compounds

See also

References