Mercury Fulminate decomposition temperature

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... 

Chemical stability and behaviour at higb temperatures. Mercury fulminate undergoes marked thermal decomposition even at 50°C. Rathsburg [37] found that a sample of the technical product stored at 50-60°C for 6 months in a dry atmo-... 

Singh [24] noticed that when heated for a few minutes at a temperature nearing that of immediate decomposition mercury fulminate crystals undergo decomposi-... 

When crystals of mercury fulminate are heated at lower temperatures the decomposition reaction is localized mainly around lattice defects such as growth marks on the surface of crystals or points where dislocations emerge at the surface (Fig. 32(c)). 

The ignition temperature, when heated at the rate of 20°C/min, is 205-208°C i.e. higher than that of fulminate, but decomposition becomes evident on heating at a temperature slightly exceeding 100°C. The substance is exploded by a drop three times less than that of mercury fulminate. 

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. 

However, when lead azide, lead styphnate, mercury fulminate, RDX, TNT, and PETN were subjected to bombardment with a negative pion beam, no explosions or decompositions were observed for any of the explosives. The analysis had predicted initiation only for RDX. Also it had indicated that nuclear fission events would produce higher energy densities and greater temperature increases than were actually observed. 

Fourcroy prepared a fulminating mercury by digesting red oxide of mercury in ammonia water for 8 or 10 days. The material became white and finally assumed the form of crystalline scales. The dried product exploded loudly from fire, but underwent a spontaneous decomposition when left to itself. At slightly elevated temperatures it gave off ammonia and left a residue of mercury oxide. 

Many authors stated that keeping most of the solutions of mercuric fulminate for a longer time leads to the decomposition of the substance. According to Solonina [28] a solution of mercuric fulminate in 22% aqueous ammonia produced a decomposition of the dissolved substance and mercuric oxide precipitated after 12 hours of keeping the solution at room temperature. Pyridine — a good solvent of mercuric fulminate - may also bring about decomposition Nvith a precipitation of metallic mercury [26, 28]. Also a yellow coloured precipitate may be formed with a low content of Hg (ca. 58.5%) [1 ]. 

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