Silver nitrite, decomposition

A kinetic study of the previously reported substitution of aromatic nitro groups by tervalent phosphorus has established an aromatic 5n2 mechanism. Similarities in values of activation energies, and in relative reactivities of phosphite and phosphonite esters, between this displacement and the Arbusov reaction suggest a related mechanism (31), while the lack of reactivity of p-dinitrobenzene is attributed to the need for intramolecular solvation (32). The exclusive formation of ethyl nitrite, rather than other isomers, is confirmed from the decomposition of triethoxy-(ethyl)phosphonium fluoroborate (33) in the presence of silver nitrite. A mechanism involving quinquevalent phosphorus (34) still seems applicable, particularly in view of the recent mechanistic work on the Arbusov reaction. ... 

An attempt to prepare cyclonite by reacting the substance (III) with silver nitrite also failed, as it resulted in total decomposition of the molecule. 

Small, yellowish, acicular crystals, soluble in about 300 parts of cold water. Silver nitrite is more readily soluble in hot water, but suffers partial decomposition therein. 

P. C. Ray said that the crystals of mercurous nitrite are sulphur-yellow. The sp. gr. is 5-925, and the mol. vol. 83-04. He said that the salt develops nitric oxide at 100°, but P. C. Ray and A. C. Ghosh found that the decomposition begins at 140°, and is completed at 247°. When a thin layer of the nitrite is heated in vacuo, to 195°, P. C. Ray and J. N. Sen did not obtain a complete decomposition, and estimated that that would require a temp, of 250°. They consider that the results of the analysis of the decomposition products are in agreement with E. Divers and T. Shimidzu s observations on the thermal decomposition of silver nitrite, the... 

Potassium nitrite, KN02.—The nitrite is made by the reduction of potassium nitrate by heating it alone, or with metals such as lead and iron, or with substances containing sulphur or carbon. It is also formed from potassium nitrate by electrolysis with a silver cathode and a copper anode, the yield being almost quantitative.8 The pure salt can be obtained by precipitating the aqueous solution with methyl alcohol.9 Another method for the production of the nitrite depends on the double decomposition of silver nitrite and lithium chloride.10... 

With the exception of silver nitrite, which is only slightly soluble, nitrite salts readily dissolve in water. The alkali metal nitrites and ammonium nitrite are hygroscopic. While sodium nitrite melts without decomposition, most other nitrites decompose before reaching the melting point (Ba(N02)2 > 593 K, AgN02 > 413 K, Hg(N02)2 > 348 K). Ammonium nitrite decomposes above 333 K, sometimes explosively, to dinitrogen and water ... 

Histidine hydrochloride (2 g.) is suspended in concentrated hydrochloric acid and slowly treated with silver nitrite (3 g.). After removal of excess nitrous acid and silver chloride, the liquid is concentrated to a sirup, which is taken up in alcohol, treated with an excess of alcoholic trimethylamine solution, and kept at 80° for 8 hours. After removal of the alcohol the product is precipitated with phosphotungstic acid. The phosphotungstate is decomposed with barium hydroxide in the usual manner, and the solution of the base thus obtained is strongly concentrated to remove trimethylamine, treated with hydrochloric acid, and the resulting chloride is taken up in alcohol and precipitated with chloroplatinic acid. It is finally converted into the chloroaurate, m.p. 183° with decomposition (14). 

Probably the most academically dramatic use of metal Tc-complex formation was demonstrated by the trapping of the cyclobutadiene-silver nitrite complex. Many subsequent cyclobutadiene derivatives were isolated and proved to be rather stable complexes. For example, tetraphenylcyclo-butadieneiron tricarbonyl melts without decomposition at 234° and tetra-phenylcyclobutadiene 7r-cyclopentadienyl cobalt melts at 256°C under nitrogen. Upon examination of the electronic configuration the stability of these complexes often can be predicted. 

The chlorates, like the nitrates, are all readily soluble in water lead and silver chlorites, like the corresponding nitrites, are sparingly soluble salts and lead perchlorate is the only salt which does not easily dissolve. As already mentioned, chloric acid is readily decomposed when its aqueous solution is warmed chlorous acid is still less stable but perchloric acid, which may be prepared by distilling together potassium perchlorate with concentrated sulphuric acid, is relatively stable, seeing that it can be distilled without decomposition. It is an oily liquid, with acid taste it is apt to explode when brought into contact... 

Potassium tetranitrodiamminecobaltate(III) is a lustrous yellow to brown solid, the exact color depending on the crystal size. It is only very slightly soluble in cold water the solubility at 100° is about 5 g./lOO ml. of water. Prolonged contact with water at temperatures above 50 to 60° causes decomposition. Treatment with excess 10% aqueous oxahc acid yields potassium dinitrooxalatodiamminecobal-tate(III). Silver or mercury (I) nitrate causes the precipitation of the corresponding sparingly soluble metal salts of the anion. The free acid is also relatively stable. Aqueous ethylenediamine displaces nitrite from the complex to give the nonelectrolyte trinitro (ethylenediamine) amminecobalt-(III). ... 

In the new procedure described below the potassium dinitrodiglycinatocobaltate(III) is prepared by a simpler, direct method consisting of the oxidation of cobalt(II) to cobalt(III) in the presence of potassium glycinate and potassium nitrite. The corresponding silver and mercury (I) salts are obtained by double decomposition of the potassium salt with silver and mercury(I) nitrates, respectively. 

Methyl nitrite on an Ag(lll) surface undergoes decomposition on irradiation at X > 365 nm or by 50 eV electrons. The decomposition involves the extrusion of NO from both irradiation methods but X-ray irradiation (50 eV) also supplies evidence for the formation of methyl radicals, formaldehyde and methanol48. The orientation of the methyl nitrite monolayer on the silver is consistent with the NO extrusion process49. f-Butyl nitrite also undergoes loss of NO when a thin film assembled on silver(l 11) is irradiated at 355 nm50. 

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