Silver nitrate, reaction with Subject

In the Breathalyzer test, the subject blows into a tube connected to a vial. The exhaled air collects in the vial, which already contains a mixture of sulfuric acid, potassium dichromate, water, and the catalyst silver nitrate. The alcohol reacts with the dichromate ion in the following redox reaction. 

The rates of reaction of hypophosphorous acid with iodine bromine ", chlorine ", iodine chlorides , iodate , selenious and tel-lurous acids, silver nitrate , cupric chloride and mercuric chloride" (all forming phosphorous acid or phosphites) have been measured, and the results of the earlier work summarized clearly" . All the data are consistent with the hypothesis that there is prior transformation to some reactive form (I). This form (I) does not discriminate very effectively between different oxidants and thus the oxidation steps are presumed to have rates close to the diffusion-controlled limit. The rates of formation of I deduced in these studies are close enough to the rates of deuterium and tritium exchange for the residual difference to represent an isotope effect. Mitchell wrote the formula H5PO3 for I. Others have supposed it to be a tautomer e.g. HPO(OH)2. Both the isotopic exchange results and the oxidation studies require that its formation and decomposition be subject to acid catalysis. For the general mechanism... 

When 5-methylene-2,3,4,5-tetrahydro-1 -benzothiepine (111) was subjected to ring expansion reaction conditions (treatment with silver nitrate in the presence of iodine in methanol), intramolecular attack by sulfur at the initially formed halomethyl group led to the bicyclo[3.2. Ijoctane intermediate (112), which yielded the benzothiophene derivative (113) without formation of any ring expansion products (Scheme 15) <89TL4279>. 

Reaction with alcoholic silver nitrate has been used as a qualitative test for the ditin linkage, and a variety of compounds, including aryl derivatives, have been shown to deposit a silver mirror on treatment with the reagent (195, 198, 200, 215, 244). Potassium permanganate is also reduced readily (200,265). Hexaphenylditin has been shown to react virtually quantitatively to produce triphenyltin hydroxide when subjected to the action of potassium permanganate in acetone solution (265). 

The montmorillonite used in this study was the less than 2pm particle-size fraction of bentonite from Milowice, Poland The cation exchange capacity (CEC) of the clay is 76 meq per 100 g. The clay was subjected to exchange with Na+ ions by stirring in 1 TV NaCI solution for 24 h followed by repeated washing with 1 N NaCl. The resulting suspension was washed several times with distilled water until free of Cl ions as indicated by lack of reaction of the supernatant with silver nitrate solution. The solid separated by centrifugation was dried in air at 353 K. This material is henceforth referred to as Na-mt. 

Most workers have preferred to prepare stable derivatives prior to analysis. For example, cyclopropene fatty acids can be subjected to hydrogenation, or reaction with silver nitrate [449] or methanethiol [746]. Silver nitrate in anhydrous methanol reacts with cyclopropene rings in about 2 hours at 30 C to form predominantly methoxy ether but with some enonic derivatives, which appear as twin peaks (because of reaction on either side of the ring) on analysis by GC [99,241,281]. An application of this procedure to the analysis of kapok seed oil is illustrated in Figure 5.14. Alternatively, a brief reaction with hydrazine will selectively reduce the cyclopropene compounds to the more stable cyclopropanes by examination by GC before and after the reaction, the small amounts of natural cyclopropane components can also be identified [194]. 

Official Preparation of Antimony Trioxide (antimonii oxidum) — Sulplude of antimony in very fine powder, 4 oz. troy hydrochloric acid, 18 oz, troy nitric acid, 1 oz. troy liquor ammonise, IJ fl. oz. distilled water. The sulphide is put into a flask containing hydrochloric acid, and is then digested by means of a sand-bath until effervescence ceases. Thai add nitric acid gradually. When the nitrous acid vapours have ceased to be given off, the solution is allowed to cool. Add half a pint of water and filter. Pour the filtered liquid gradually into 12 pints of water, constantly stir it, and allow the precipitate to subside Decant the liquid and wash the precipitate twice- on each occasion with 8 pints of water. Then transfer it to a muslin filter to drain, and wash it until the acid reaction ceases. Introduce it into a vessel and subject it to the action of liquor ammonias for two hours. Then transfer it to a muslin filter and wash it until the filtrate gives no precipitate when silver nitrate is added. Dry it finally in a gentle heat. 

Other derivatives that are not ureides may, however, also be subject to this reaction. This is the case, for example, of theophylline, which is endowed with a weak acidic character due to its mobile hydrogen brought by the nitrogen in position 7. Theophylline s pK value is 8.6. To perform the titration, an excess of silver nitrate is added and the titration is carried out by sodium hydroxide. The indicator is bromothymol blue. 

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