Mercury fulminate, with

N 49 01% wh ndls, sol in warm w. Structure not known. Prepd by heating Mercury Fulminate with ammonia at 70°. Completely decomposed to CO2 and NHa by dil HCl at 150°. Neutral in water, but will react with metal oxides giving, eg, a Silver salt, Ag/)6HgN903 Refs 1) Beil 1, 723 2) A. Steiner, Ber 8 ... 

Pyridine is also a good solvent for mercury fulminate. 14.5 g of mercury fulminate may be dissolved in a 1 g of pyridine on moderate heating. The fulminate may by recovered if the solution is poured into water. Large crystals, an addition compound of mercury fulminate with pyridine, then separate. This compound loses pyridine on drying. 

Mercury fulminate dissolves readily in an aqueous solution of potassium cyanide to form a complex compound from which it is reprecipitated by the addition of strong acid. It dissolves in pyridine and precipitates again if the solution is poured into water. A sodium thiosulfate solution dissolves mercury fulminate with the formation of mercury tetrathionate and other inert compounds, and this reagent is used both for the destruction of fulminate and for its analysis.10 The first reaction appears to be as follows. 

Although the gas is extremely stable to heating, cyanogen is early reported detonable, presumably as liquid, by mercury fulminate. With AHf (g) +307.9 kJ/mol, 5.91 kJ/g, it is the thermal stability that is the surprise. 

Swedish inventors Emmanuel Nobel and his son Alfred took an interest in this powerful liquid explosive and produced it commercially in 1862. However, its transportation and its handling were very hazardous, and eventually Alfred Nobel discovered that NG absorbed into a granular type of material (kieselguhr) was still explosive, but was much safer to handle and use than the straight liquid. This new invention, called dynamite, was difficult to ignite by the usual methods used for pure NG. Therefore, also in 1867, Alfred Nobel devised the blasting cap using mercury fulminate. With this development dynamite became the foundation of the commercial explosives industry. 

Percussion caps serve as primers for propellant charges. In mechanical percussion caps, a friction-sensitive or impact-sensitive priming charge (containing, e.g., mercury fulminate with chlorates or lead trinitroresorcinate with Tetrazene) is ignited by the mechanical action of a firing pin. 

Nitroglycerin was discovered by Ascanio Sobrero, in 1846. Its danger made it a laboratoiy curiosity until Alfred Nobel improved it along with other inventions such as the blasting cap ing mercury fulminate. 

Gamer and Hailes [462] postulated a chain branching reaction in the decomposition of mercury fulminate, since the values of n( 10—20) were larger than could be considered consistent with power law equation [eqn. (2)] obedience. If the rate of nucleation is constant (0 = 1 for the generation of a new nuclei at a large number of sites, N0) and there is a constant rate of branching of existing nuclei (ftB), the nucleation law is... 

With polyhaloalkanes, potassium forms mixtures that detonate on impact. The potassium/carbon tetrachloride mixture is hundred and fifty to two hundred times more sensitive than mercury fulminate. A simple door slam can cause its detonation. 

When used in detonators, mercury fulminate is frequently mixed with 10 or 20% of potassium chlorate. Such mixtures have a better oxygen balance and therefore give improved and more reliable initiation of other explosives. 

The initiating explosive used must ignite with certainty from the spit of a safety fuse. It must be remembered that the intensity of the spit can be reduced if the safety fuse is not cut squarely and also that the fuse may in practice not always be fully inserted into the detonator. Lead azide by itself is not sufficiently easily ignited to give a satisfactory plain detonator and it is therefore used in admixture with lead styphnate, which is very readily ignited by flame. The proportions of such mixtures vary from 25 to 50% of lead styphnate. Mercury fulminate and diazodinitrophenol are sufficiently sensitive to flame not to require such additives. 

Attempts to follow a published procedure for the preparation of 1,3 -dithiole-2-thione-4,5-dithiolate salts [1], involving reductive coupling of carbon disulfide with alkali metals, have led to violent explosions with potassium metal, but not with sodium [2], However, mixtures of carbon disulfide with potassium-sodium alloy, potassium, sodium, or lithium are capable of detonation by shock, though not by heating. The explosive power decreases in the order given above, and the first mixture is more shock-sensitive than mercury fulminate [3],... 

Mercury fulminate, readily formed by interaction of mercury(II) nitrate, nitric acid and ethanol, is endothermic (AH°f (s) +267.7 kJ/mol, 0.94 kJ/g) and was a very widely used detonator. It may be initiated when dry by flame, heat, impact, friction or intense radiation. Contact with sulfuric acid causes explosion [1], The effects of impurities on the preparation and decomposition of the salt have been described [2],... 

The compound, precipitated by interaction of hexamethylene tetramine and acidic 30% hydrogen peroxide, is a heat- and shock-sensitive powerful explosive when dry, much more shock sensitive than mercury fulminate. It explodes in contact with bromine or sulfuric acid. 

Mixtures of the alloy with silver oxide or mercury oxide are shock-sensitive powerful explosives. The red form of mercury(I) oxide gives mixtures 40 times, and the yellow form 140 times as sensitive as mercury fulminate. 

This primary explosive is created by adding lead acetate to a solution of sodium or ammonium azide. Lead azide has a good shelf life in dry conditions but is unstable in the presence of moisture, oxidizing agents, and ammonia. It is less sensitive to impact than mercury fulminate, but more sensitive to friction. Since lead azide is a nonconductor, it may be mixed with flaked graphite to form a conductive mixture for use in low-energy electronic detonators. 

Mercury fulminate (C2N202Hg) is one of the most important primary explosives. It is usually found in the form of a gray powder, is sensitive to impact and friction, and is easily detonated by sparks and flames. It is desensitized by the addition of water, but is very sensitive to sunlight. It reacts with metals in moist environments. It is created by treating a solution of mercuric nitrate with alcohol in nitric acid. Its most important explosive property is that it easily detonates after initiation.10... 

By further nitration with more concentrated acid o- and p-nitro-phenols are converted into the same 2 4-dinitrophenol, and finally into picric acid. Polynitro-derivatives of benzene, such as picric acid and trinitrotoluene, can be caused to explode by detonation with mercury fulminate or lead azide. (The formulae of these two compounds should be written.) They are endothermic, i.e. the oxygen of the nitro-group can oxidise carbon and hydrogen within the molecule and heat is liberated. This intramolecular combustion is rather considerable in the case of picric acid, which is decomposed in accordance with the equation ... 

The metal fulminates are all powerfully explosive. Of several salts examined, those of cadmium, copper and silver were more powerful detonators than mercury fulminate, while thallium fulminate was much more sensitive to heating and impact. Formally related salts are also explosive [1]. Sodium, potassium, rubidium and caesium fulminates are all easily detonated by feeble friction or heat. They all form double salts with mercury(II) fulminate which also explode readily, that of the rubidium salt at 45 °C [2],... 

The need for great care to avoid the possibility of detonation of perchloryl compounds by exposure to shock, overheating or sparks is stressed. The compounds are generally more sensitive to impact than mercury fulminate and are of comparable sensitivity to lead azide [1], A range of highly explosive alkyl perchlorates [2] and perchlorylamines [3] have been prepared by interaction of dichlorine heptaoxide with alcohols or amines in carbon tetrachloride solution. The solutions of the products were not sensitive to mechanical shock and could... 

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