Mercury oxalate, decomposition

The composition of the primary products was determined by choosing the decomposition scheme whose enthalpy (ArH ) would agree with the experimental value equal to i/E. For mercury oxalate decomposing only to gaseous... 

The calculated vaporization coefficients of the oxalates are listed in Table 16.66. The lowest values of Ov, of the order of 10, are characteristic of silver and mercury oxalates. Both compounds are explosives. The enthalpies of the exothermic (at h q)othetical equilibrium) decomposition of these compounds are —112.5 and —114.2 kJ moP, respectively, so that the equilibrium pressure of CO2 at 400 K should reach 10 bar. However, the decomposition actually occurs considerably more slowly, because the composition of the primary vaporization products is essentially non-equilibrium. 

Aqueous solutions of organic acids such as formic, acetic, and oxalic, decompose mercury fulminate, forming the corresponding mercuric salts. On the other hand, the action of dilute inorganic acids involves decomposition with formation of C02. 

Mercuric oxalate appears to undergo decomposition by a somewhat different mechanism with the formation of mercury and mercurous oxalate as intermediate products before full decomposition occurs (Prout and Tompkins [81]). 

The methyl ester yields a similar compound which melts with partial decomposition at 123° C., and is less soluble in ether than the ethyl derivative. The methyl compound is decomposed by water at ordinary temperatures into mercury, nitrogen, methyl alcohol, oxalic and glycollie acids. 

The decomposition of mercury(II) oxalate [96] yields the metal, which is volatile under reaction conditions, mercury(II) oxide and both CO and COj. nr-time curves were sigmoid (453 to 478 K). The reaction initially spread rapidly over the surfaces of crystalhtes (ii, = 107 kJ mol ) from a number of reaction centres. Subsequently the rate was controlled by the inward advance of a reaction interface (f, = 155 kJ mol ). The reaction rate was not markedly influenced by the presence of gaseous or sohd products. The initial process is accelerated by radiation, which is believed to yield the mercury(I) salt following electron transfer. 

OXALIC ACID (144-62-7) CjHjO. HOOCCOOH Combustible solid heat-sensitive. (combustible <215 F/101°C. Fire Rating 1). Exposure to elevated temperatures, hot surfaces, or flames causes decomposition and the formation of toxic and flammable formic acid and carbon monoxide. Hygroscopic the solution in water is a medium-strong acid. Violent reaction with strong oxidizers, acid chlorides alkali metals bromine, furfuryl alcohol hydrogen peroxide (90%) phosphorus trichloride silver powders sodium, sodium chlorite sodium hypochlorite urea + heat (forms NHj gas, CO2 and CO may explode). Mixture with some silver compounds forms explosive salts of silver oxalate. Incompatible with caustics, mercury, urea. On small fires, use dry chemical powder (such as Purple-K-... 

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