Explosive properties mercury fulminate

Tetrazene (C2H8N10O) is a pale yellow crystalline explosive generally used in ignition caps, where a small amount is added to the explosive composition to improve its sensitivity to percussion and friction. Tetrazene is not suitable for filling detonators because its compaction properties make the transition from burning to detonation very difficult. This primary explosive is stable in ambient temperatures. Its ignition temperature is lower and it is slightly more sensitive to impact than mercury fulminate. 

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... 

While little serious research has been conducted on the properties of TATP, this is not the case for HMTD. As previously mentioned, tests conducted by U.S. Army ordnance illustrated that HMTD was a tremendously powerful initiating explosive, exhibiting between three and four times the strength of mercury fulminate. Unfortunately, HMTD was too thermally unstable and too chemically... 

According to Kaufman [52] strong y-radiation (on average 105r per hour) can decompose mercury fulminate. Mercury fulminate evolves large amounts of gas during irradiation and eventually loses its explosive properties. 

Martin [64] examined the initiating properties of certain fulminates, and found that silver, cadmium and copper fulminates have stronger initiating properties than mercury fulminate. Table 25 and Fig. 45 show the figures obtained by Wohler and Martin [65], expressed as the smallest amounts of the fulminate of different metals necessary to produce detonation of various high explosives. 

This substance was the first diazo compound to be discovered. It was prepared by Griess [11] by diazotizing picramic acid. Its explosive properties attracted the attention of Lenze [12] who found it to be as valuable as mercury fulminate in spite of its higher sensitiveness to impact. This compound is also of interest as being the first initiator containing no heavy metals. It has now been utilized in the United States of America and Japan as a component of initiating charges in detonators and caps. 

Caution 1 A serious explosion of the perchlorate has been reported. The perchlorate is almost as sensitive to friction as mercury fulminate. However, the (Corresponding tetrafluoroborate is safe to handle and is chemically similar. 2,4,6-Triphenylpyrylium perchlorate also has explosive properties. 

Mercury fulminate was first prepared in the 17th century by the Swedish-German alchemist, Baron Johann Kunkel von Lowenstern. He obtained this dangerous explosive by treating mercury with nitric acid and alcohol. At that time, Kunkel and other alchemists could not find a use for the explosive and the compound became forgotten until Edward Howard of England rediscovered it between 1799 and 1800. Howard examined the properties of mercury fulminate and proposed its use as a percussion initiator for blackpowder and in 1807 a Scottish Clergyman, Alexander Forsyth patented the device. 

The most important explosive property of mercury fulminate is that after initiation it will easily detonate. On detonation, it decomposes to stable products as shown in Reaction 2.5. 

Medard [23a] examined the explosive properties of methyl-a-D-glucopyranoside tetranitrate prepared according to Fleury et al. [12]. The product requires a relatively weak initiator, e.g. 0.25 g of mercury fulminate suffised to detonate a sample of the substance of density 1.10. Only the cast product (density 1.65) requires a strong detonator (over 1.5 g fulminate). 

Tetracene explodes readily from flame without appreciable noise but with the production of much black smoke. Rinkenbach and Burton,61 who have made an extended study of the explosive properties of tetracene, report that it explodes in 5 seconds at 160° (mercury fulminate 190°). They found that it is slightly more sensitive to impact than mercury fulminate an 8-inch drop of an 8-ounce weight was needed to explode it, a drop of 9-10 inches to explode fulminate. 

Properties White, pulped fibers, having a nitrogen content of 13.2-13.5 per cent, only partly soluble in ether-alcohol, completely soluble in acetone. Deteriorates under heat, but is stable in moist condition. In fiber form it is a high explosive gelatinized, it is a low-order explosive. The dry fiber can be detonated with mercury fulminate. Dry guncotton can be used as initiator for the detonation of wet guncotton. Rate of detonation (13 per cent nitrogen) 6300 m/sec. (d = 1.7). 

Properties White to buff-colored crystalline powder. Sp. gr. 4.80. One of the most stable initiators. Less sensitive to blows than mercury fulminate. Too insensitive to be used alone where initiation is by impact of firing pin. Not easily decomposed by heat. Instantaneous flash point over 350°. Forms a supersensitive explosive in contact with copper. 

Mercury in Abel heat test, 77 in mercury fulminate, estimation of, 60 in smokeless powders, estimatioin of, 54 Mercury fulminate, analysis of mixtures containing, 15a explosive properties of, 153 mixture fur )ercu5sioa caps,... 

Nitro Compounds as Explosives.—Nitro compounds prepared from aromatic hydrocarbons and certain of their derivatives were very important explosives used in the recent war. The compounds differ markedly in the properties which are characteristic of explosives namely, (1) sensitiveness to shock, (2) explosive force, and (3) the velocity of the explosion through the substance. If (1) is very high the explosive can not be transported very safely (2) determines the amount of the explosive to be used if (3) is very high the pressure is developed to its maximum so suddenly that rupture of the gun in which it is used may take place. Substances which are very sensitive to shock are used as detonators or boosters a small amount of the material is exploded by the trigger and the explosive wave set up causes the explosion of the less sensitive material. Mercury fulminate, lead azide, Pb(Ns)2, and several nitro derivatives of aniline (see below) are used for this purpose. 

Explosive properties Harmless when moist, quite sensitive to rubbing when dry or moistened with ether. Explodes when placed in a flame. Six times stronger than Pb(N3)g and 450 times stronger than mercury fulminate when used as a detonator. 

Kekule incorrectly represents fulminic acid as a nitro-compound, Cg(N04)(C2N)H2, which explains its explosive properties. He found that mercury fulminate treated with chlorine gas forms chlorpicrin, cyanogen chloride, and mercuric chloride ... 

As opposed to alkaline azides which do not have properties of explosives, alkaline fulminates are mostly reported as highly sensitive and explosive substances [8,107, 108] even though one source mentioned sodium fulminate as not so sensitive (impact sensitivity for NaCNO to be 32 cm with 0.5 kg hammer compared to 7.5-10 cm MF under the same conditions) [27]. Sensitivity of these fulminates is reported as extreme and handling a hazardous operation [8, 107, 108]. Extreme sensitivity is further reported for the rubidium and cesium salts. Alkaline fulminates undergo explosion when initiated by flame, even in small amounts, whereas mercury fulminate only deflagrates. The exact sensitivity data are, however, not reported in this work [107]. Sensitivity of cadmium fulminate to impact is about the same as that of MF sensitivity of thallium fulminate is higher [15, 57]. 

Fulminic Acid, C=N--OH.—Salts of this acid are obtained when nitric acid, alcohol, and mercury or silver are brought together in certain proportions. Mercuric fulminate, (CNO)2Hg, is prepared for use in percussion caps, which are used to explode gunpowder, dynamite, and other explosives. Free fulminic acid is a very unstable volatile liquid. It resembles closely hydrocyanic acid in odor and poisonous properties. 

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