Oxalate silver

Phenylazoimide Silicon hydride Silver oxalate Sodium chlorite Trimtrobenzaldehyde... 

Silver Oxalate. Ag2C204, mw 303.78, wh cryst powd mp, decomps violently between 130° 190° (see below) d 5.03g/cc. Sol in 24000p of w, moderately coned nitric acid, and ammonia. Can be prepd by mixing cold solns of oxalic acid and Ag nitrate (Refs 1, 2 6)... 

Various mechanisms involved, as in the decompo sition of silver oxalate or silver azide... 

Silver is incompatible with oxalic or tartaric acids, since the silver salts decompose on heating. Silver oxalate explodes at 140°C, and silver tartrate loses carbon dioxide. 

Kabanov, A. A. etal., Russ. Chem. Rev., 1975, 44, 538-551 Application of electric fields to various explosive heavy metal derivatives (silver oxalate, barium, copper, lead, silver or thallium azides, or silver acetylide) accelerates the rate of thermal decomposition. Possible mechanisms are discussed. 

CopperQ oxalate, 0622 Iron(III) oxalate, 2065 Mercuiy(II) oxalate, 0982 Potassium dinitrooxalatoplatinate(2—), 0988 Silver oxalate, 0572 See Other HEAVY METAL DERIVATIVES... 

Silver is a white, ductile metal occurring naturally in its pure form and in ores (USEPA 1980). Silver has the highest electrical and thermal conductivity of all metals. Some silver compounds are extremely photosensitive and are stable in air and water, except for tarnishing readily when exposed to sulfur compounds (Heyl et al. 1973). Metallic silver is insoluble in water, but many silver salts, such as silver nitrate, are soluble in water to more than 1220 g/L (Table 7.3). In natural environments, silver occurs primarily in the form of the sulfide or is intimately associated with other metal sulfides, especially fhose of lead, copper, iron, and gold, which are all essentially insoluble (USEPA 1980 USPHS 1990). Silver readily forms compounds with antimony, arsenic, selenium, and tellurium (Smith and Carson 1977). Silver has two stable isotopes ( ° Ag and ° Ag) and 20 radioisotopes none of the radioisotopes of silver occurs naturally, and the radioisotope with the longest physical half-life (253 days) is "° Ag. Several compounds of silver are potential explosion hazards silver oxalate decomposes explosively when heated silver acetylide (Ag2C2) is sensitive to detonation on contact and silver azide (AgN3) detonates spontaneously under certain conditions (Smith and Carson 1977). 

Explosion Retardation. The sample-size effects of the explosion retardation of mercury and silver oxalates and fulminates are discussed... 

As early as 1883 Berthelot [75] noticed that some salts of oxalic acid (e.g. mercuric or silver oxalates) have the properties of primary explosives. 

Thus it is similar to the decomposition of azides. There have been several papers on silver oxalate — Ag2C204. Macdonald and Hinshelwood [76] confirmed the Berthelot equation, according to which the only products of decomposition of silver oxalate are metallic silver and C02. 

Benton and Cunningham [77] found that the rate of thermal decomposition of silver oxalate may be increased by previously exposing it to ultra-violet radiation. 

During the thermal decomposition of silver oxalate, fragments of metallic silver are formed. This has been confirmed by conductivity measurements (Macdonald and Sandison [78]) or by X-ray examination (Griffith [79]). 

Tompkins [80] investigated the thermal decomposition of silver oxalate at 110— 130°C. Its decomposition, in his opinion, is similar to that of barium azide. 

Silver oxalate is a colourless, crystalline substance which on heating undergoes an exothermic decomposition. The reaction begins at a little over 100 °C and easily becomes explosive. It was noticed quite early that samples prepared in the presence of an excess of oxalate were less stable thermally than those prepared using stoichiometric amounts of oxalate and silver ions. The thermal decomposition of silver oxalate into silver and C02 has subsequently been studied under varying conditions of preparation, decomposition environment and preirradiation.258,259... 

The crystal structure of silver oxalate may be considered to be made up of a series of chains held together in sheets by Ag—O crosslinks (28). Ag—O bond lengths were 217-230 pm and between chains the Ag—O separation was 258-261 pm.260... 

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