Metal fulminates mercury fulminate

Reactions with metals. When mercury fulminate is boiled with water containing metallic suspensions, the majority of metals (e.g. aluminium, zinc, copper), form their fulminates and mercury is precipitated. Reaction can also occur at room temperature, except with nickel. Other metals may be ranged according to increasing reactivity silver, tin, bismuth, cadmium, iron, lead, copper, zinc, brass, aluminium. With aluminium, the reaction takes only a few hours, yielding a large amount of A1203. 

Fulminates —C=N O Metal fuminates Mercury fulminate sodium fulminate... 

Initiators. Explosives such as mercury fulminate and certain metallic azides which are extremely sensitive to mechanical shock, and are accordingly used in small quantities in detonators to initiate the explosion of larger masses of less sensitive material. 

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],... 

See other endothermic compounds, mercury compounds, metal fulminates... 

This priming explosive, as sensitive as mercury fulminate, is much more powerful than metal-containing initiators. 

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... 

Although the description fulminating is not used and thus confusion with the fulminate not caused, mercury also forms explosive compounds of similar nature. The nitride (ibid.) is the most common and can be formed from the metal and ammonia in some circumstances, causing accidents where mercury manometers are used with ammonia. Halo-hydroxy- and oxy-nitrides can also be involved [3], See METAL FULMINATES, GOLD COMPOUNDS, A-METAL DERIVATIVES, PRECIOUS METAL DERIVATIVES, SILVER COMPOUNDS... 

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],... 

Primary explosives are sensitive to modest stimuli such as heat, spark, or friction application of the correct stimulus will lead to a detonation. The primary explosives used in detonators are typically extremely sensitive but not particularly powerful common examples are mercury fulminate, lead azide, and lead styphnate. In principle, the heavy metals present in most primary explosives should be a good cue for detection however, there are primary explosives that do not contain such elements. 

This class of compounds showing explosive instability deals with heavy metals bonded to elements other than nitrogen and contains the separately treated groups GOLD COMPOUNDS LEAD SALTS OF NITRO COMPOUNDS LITHIUM PERALKYLURANATES MERCURY COMPOUNDS METAL ACETYLIDES METAL FULMINATES METAL OXALATES PLATINUM COMPOUNDS PRECIOUS METAL DERIVATIVES SILVER COMPOUNDS... 

Mercury fulminate is prepared by the reaction of mercury metal with strong nitric acid and ethanol. The preparative method involves pouring a nitric acid solution of mercury(II) nitrate into ethanol. The reaction is not well understood. 

The highly substituted derivative 186, in the form of the potassium salt, has been recommended for use in detonators in place of the more dangerous mercury fulminate. l,2,3-Benzotriazine-4-thione (39, R — H) has been used in photographic transfer emulsions as an inhibitor and toning agent, and heavy metal salts of the oxygen analog 10, R = H are employed as photodevelopable emulsions. The latter compound is also claimed to be useful as a stabilizer in olefin polymers and as an antioxidant in certain other polymers. Dimeric derivatives of 10 have... 

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 ... 

A plot of logio Ed against 1/1) is almost rectilinear. Therefore, Ea may be determined by equating (EJ4.57) with the slope of the straight line. Equation 3.3 holds good for a number of explosives such as lead azide, cuprous azide, mercury fulminate, lead styphnate, barium styphnate and metal picrates and metal picramates etc. [25-30]. Thus, it appears that the determination of Ea gives a more complete picture concerning the heat sensitivity of explosives than ED or ET. 

Mercury fulminate is easy to produce, has been known since earliest times and is still widely used. The scarcity of mercury has however led to many attempts to replace this substance by something else, in particular by substances containing a different metal. Some success was achieved as a result of work of Will and Lenze [5] in 1892 on the application of heavy-metal azides as initiating agents. 

As previously stated, mercury fulminate is hydrolysed by heating in water in boiling water hydrolysis is very rapid. Farmer [31] noticed that on heating with water under pressure, mercury fulminate undergoes decomposition to metallic mercury. Marked decomposition also takes place on heating or standing for long periods at room temperature in an aqueous solution of ammonia or potassium... 

Strong alkalis decompose mercury fulminate easily. Heating with aniline leads to the formation of phenylurea, diphenylguanidine and metallic mercury (Steiner [34]). 

A similar reaction was observed when mercury fulminate was kept in contact with metals in a damp atmosphere. Aluminium gave a white bloom after only four... 

According to various authors, the ignition temperature of mercury fulminate is 187-190°C on rapid heating on heating at a rate of 5°C/min it is 160-165°C. A test sample, when thrown onto a metallic surface heated to 215°C, explodes... 

Mercury fulminate has a sweetish metallic taste. When administered orally it is as poisonous as the majority of mercury compounds. Since, however, it is very sparingly soluble in water its toxicity through contact with the skin is insignificant. Nor is it toxic to lower plants, e.g. moulds often form on the moist bags in which mercury fulminate is stored. 

The other fulminates are of no practical value. They are prepared from mercury fulminate either by reacting the metal amalgam with a suspension of mercury fulminate in water (this is applicable to the majority of metals, including the alkali metals, or simply by the action of the metal itself (e.g. zinc or thallium) which displaces mercury from mercury fulminate (also in water). For example, chips of thallium, zinc, or copper are allowed to stand for some time in a suspension of mercury fulminate in water, the corresponding metal fulminate is gradually formed. 

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. 

Tetrazene is stable at temperatures up to 75°C. At 100°C it undergoes marked decomposition. The ignition temperature of tetrazene is lower than that of mercury fulminate. On a metal plate, heated to 160°C, it explodes after 5 sec (mercury fulminate behaves in the same way at 190°C). According to Wallbaum [29] tetrazene explodes at 140°C on being heated at the rate of 20°C/min. 

At the beginning of the twentieth century the thiocyanates (rhodanates) of certain metals (e.g. mercury, copper) were recommended as components of cap compositions with potassium chlorate. The rhodanates were intended as a substitute for mercury fulminate, but only lead rhodanate acquired any practical significance. 

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