Mercury(II) fulminate

• Mercury (II ) fulminate
• Quecksilberfulminat
• Quecksilberdifulminat
• Quecksilbercyanat

White- gray powder

Fixed

4.42 g · cm -3

Explodes above 160-180 ° C

Slightly soluble in water

Risk

0.1 mg · m-3

Template: Infobox chemical / molecular formula search available

Fulminate of mercury ( chemical: Mercury (II) fulminate ) is the mercury salt of the acid pop. It is the purest form of colorless crystals. Fulminate of mercury is poisonous and decomposes even at low mechanical or thermal stress.

History

The mercury fulminate has probably been the end of the 17th century by Kunkel of Löwenstern and other alchemists first isolated. The production of mercury, ethanol and nitric acid is first described in 1799 by the Englishman E. Howard.

Due to its distinct Initiierfähigkeit mercury fulminate at the time was the most common primary explosive. It was used in ignition and detonators. Alfred Nobel put mercury fulminate into blasting caps for detonating dynamite. This relatively safe new detonator was for the huge success of dynamite explosives. Alone in the German Empire, the annual production was about 100,000 kg of mercury fulminate in the early 20th century.

Meanwhile, mercury fulminate however, has been replaced by other substances, such as lead azide.

Production and representation

Mercury fulminate (II ) oxide with concentrated nitric acid produced by the reaction of elemental mercury or mercury in the presence of ethanol. The synthesis of larger amounts of mercury fulminate requires strict security precautions and must be performed by trained specialist staff.

For the preparation of small quantities that described in 1901 by the Italian Angelico method for silver fulminate can be used. Instead of ethanol, the reaction is carried out here with aqueous solutions of malonic acid and sodium nitrite.

Impurities by -products can be removed by one or more recrystallizations of ammonia solution. Fulminate of mercury from aqueous solutions crystallized as the hemihydrate Hg ( CNO) 2 · ½ H2O from.

Properties

Physical Properties

Mercury fulminate is good in hot water, ethanol and nitric acid, in cold water, however, only poorly soluble.

Chemical Properties

Even at a low mechanical or thermal stress decays mercury fulminate explosive. This produces elemental mercury, nitrogen and carbon monoxide:

Here, the decay by tamping or ignite larger amounts can easily turn into a detonation (v = 5000 m / s).

Since the explosion of a cloud of atomic, toxic mercury vapor is formed, it is no longer used as an explosive today.

Crystal structure

Studies on the crystal lattice of the fulminate of mercury have been carried out in the 1930s. Only in 2007, clear results were obtained. Mercury fulminate is therefore far from orthorhombic. The Hg - atoms and the two carbon atoms are surrounded - as already suggested - linearly arranged, so that the molecular arrangement of plugged ONC Hg CNO is confirmed.

Comparison image of Qualitätsextrema

High-purity mercury fulminate

Safety

Mercury fulminate is an initiating explosive and therefore particularly explosive. It can come through sources or mechanical action such as friction or shock to the explosion, but also by exposure to radiation, by drying or contact with other chemical compounds, such as sulfuric acid.

Mercury fulminate is toxic and hazardous to the environment; to aquatic organisms, there is a particularly high risk potential dar. stored underwater it is not explosive and chemically stable.