Silver fulminate

The history of silver fulminate is just as long as the history of mercury fulminate. It was probably also discovered by the alchemists Cornelius Drebbel and Johann Kunckel von Lowenstem in the seventeenth century [11, 26] even though some other authors mention BrugnatelU in 1798 [29, 35, 92] or Edward Howard a few years later [15, 35, 92, 93]. 

Silver fulminate (SF) is a white crystalline material with heat of formatiOTi 179 kJ mol [15]. It crystallizes in the form of small rosettes or star-shaped clusters. Two polymorphic forms have been reported—orthorhombic and trigonal. The crystal shape depends on reaction conditions (temperature, concentration) during sUver fulminate preparation [94]. Recrystallization from ammonia leads to needles and multiple growths of leaf-like habits [92]. Long (4—5 mm) needle-shaped crystals were prepared by Singh and investigated by X-ray analysis. It was found that the crystal is orthorhombic [95]. The crystal structure of SF was later investigated in detail by Britton and Dunitz [96, 97] and their results were confirmed by Barrick et al. [98]. Ammonium acetate solution ( 20 %) is recommended as the solvent for 

Britton and Dunitz observed that SF prepared from an ammoniacal solution after ammonia evaporation is a mixture of needles and multiple growths which tended to a leaf-like habit. The X-ray examination showed that there were two polymorphic forms present, one orthorhombic and the other trigonal, but both forms occurred as needles and as part of the leaf-like clusters. The crystal density determined by X-ray is 4.107 g cm for the orthorhombic crystals and 3.796 g cm for the trigonal crystals [96,97]. The density of SF determined formerly by Wohler and Weber is 4.09 g cm [39] or 3.938 g cm according to Singh [95] both determined it by pycnometry. 

Silver fulminate is a very poisonous substance. According to Walke it has a strong bitter metallic taste [12]. 

Just like other silver salts, SF darkens when exposed to light. It is practically insoluble in cold water and can therefore be re-crystaUized from hot water with high yields [35]. The solubility of silver fulminate in water at various temperatures is given in Table 3.3 [28, 29]. Solubility of SF in water is considerably higher than silver halogenides. 

It is used as a detonator. A potential risk of its formation may arise when silver metal, silver nitrate or any other silver salt is mixed with nitric acid and ethanol. 

White crystals of needle shape explodes on heating very slightly soluble in water (approximately 750 mg/L) (CRC Handbook 

It is one of the most powerful detonating fulminates. Its detonating power and sensitivity to heat and impact are greater than for 

While still moist the bulk of the material is transferred to a test tube even in the moist condition pressing with a metal spatula or other hard object is to be avoided. Then 2 c.c. of concentrated hydrochloric acid are poured into the test tube, when the odour of free fulminic acid can be perceived. This odour so closely resembles that of hydrocyanic acid as to make confusion possible. After half an hour the contents of the test tube are heated for a short time in the boiling water bath, 4 c.c. of water are added, silver chloride is removed by filtration, and the filtrate is evaporated to dryness on 

Silver fulminate must invariably be destroyed immediately after it is prepared. This is most readily done vrith hydrochloric acid. 

The nitrolic acids are colourless, hut dissolve in alkalis with a deep red colour because in addition to the chromogenic nitroso-group the aci-nitro-group is formed. The following formula is ascribed to the 

When methylnitrolic acid is heated in nitric acid solution it decomposes into nitrous and fulminic acids. The latter can be isolated as silver fulminate if silver nitrate is present. 

The production of fulminates (silver and mercury fulminates) from ethyl alcohol and nitric acid takes place by way of methylnitrolic acid. This question was discussed on p. 149. 

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Do not heat the silver solution or allow it to stand even for a few hours, since explosive silver fulminate may be formed. The ammoniacal solution of silver nitrate is prepared by treating 3 ml. of 0-lN silver nitrate solution with very dilute ammonia solution dropwise until the precipitate which is first formed just redissolves. 

Singh and Palkar [726] identified an initial deceleratory reaction in the decomposition of silver fulminate. This obeyed first-order kinetics (E = 27 kJ mole-1) and overlapped with the acceleratory period of the main reaction, which obeyed the power law [eqn. (2), n = 2] with E = 119 kj mole-1. The mechanism proposed included the suggestion that two-dimensional growth of nuclei involved electron transfer from anion to metal. 

Cadmium fulminate Copper fulminate Dimethylthallium fulminate Diphenylthallium fulminate Mercury(ll) mothyinitrolate Mercury(ll) formhydroxamatc Mercury(ll) fulminate Silver fulminate Sodium fulminate Thallium fulminate... 

Fulminating gold Fulminating mercury Fulminating platinum Fulminating silver Fulminic acid Furan... 

A mixture of solid silver nitrate and ethanol was handled with a metallic spatula. The mixture detonated as soon as it came into contact with the spatula. This detonation could be explained by the accidental formation of silver fulminate. However, witnesses noticed the smell of ethyl nitrate after the accident. 

When nitromethane comes into contact with silver nitrate, this can cause spontaneous explosions that are explained by the formation of explosive silver fulminate (see reaction below). 

Action of silver on nitric acid in presence of ethanol may form the readily detonable silver fulminate. 

Aqueous silver nitrate reacts with acetaldehyde to give explosive silver fulminate. 

A silvering solution exploded when disturbed. This is a particularly dangerous mixture, because both silver nitride and silver fulminate could be formed. 

Silver oxide and ammonia or hydrazine slowly form explosive silver nitride and, in presence of alcohol, silver fulminate may also be produced. 

Silver fulminate is dimeric and rather endothermic (A+361.5 kJ/dimol, 1.21 kJ/g). It is readily formed from silver or its salts, nitric acid and ethanol, and is a much more sensitive and powerful detonator than mercuric fulminate [1], The properties and applications have been reviewed [2],... 

Luchs, J. K., Photog. Sci. Eng, 1966,10, 336 Aqueous silver nitrate may react to form silver fulminate. 

A chemical polishing mixture was put into a closed glass bottle which burst 30 min later, and formation of silver fulminate was suggested. However, in absence of the silver salt such mixtures evolve gas and should not be stored in any event, especially after use for metal polishing, when the dissolved metal(s) tend to further destabilise the mixture. 

Silicon tetraazide, 4791 Silver azide, 0023 Silver cyanide, 0299 Silver fulminate, 0301... 

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