Chloric acid preparation

Reduction of aryl nitro compounds (Sec tion 22 9) The standard method for the preparation of an arylamine is by nitra tion of an aromatic ring followed by reduction of the nitro group Typical re ducing agents include iron or tin in hydro chloric acid or catalytic hydro genation... 

Iodoxybenzene has been prepared by the disproportionation of iodosobenzene,4Hi by oxidation of iodosobenzene with hypo-chlorous add or bleaching powder,7 and by oxidation of iodobenzene with hypochlorous acid or with sodium hydroxide and bromine.8 Other oxidizing agents used with iodobenzene include air,3 chlorine in pyridine,9 Caro s acid,19-11 concentrated chloric acid,15 and peracetic acid solution.13 Hypochlorite oxidation of iodobenzene dichloride has also been employed.14... 

A chloric acid digestion was used by Backer 2 391 for the preparation of tissue samples. The digest is simply diluted to determine iron, zinc, and copper. The tantalum sampling boat technique was used by Emmermann and Luecke 2531 to measure lead, zinc, and silver in prepared soil solutions. White 1S81 treated ashed plants with hydroxylamine in IN hydrochloric acid to reduce and dissolve oxides of manganese, prior to its determination by atomic absorption spectroscopy. 

The reaction is symbolized 2C102+H20=HC102+HC10S, so that the aq. soln. of N. A. E. Millon s chlorine trioxide will contain a mixture of chloric and chlorous acids and chlorine, and a soln. of the same gas in alkali lye will contain a mixture of the alkali hypochlorite, chlorite, chlorate, chloride. The chlorites are accordingly formed when soln. of chloric acid, HC103, or chlorine dioxide, C102, are partially reduced by the methods employed for the preparation of chlorine di- and tri-oxides. J. E. de Vrij 3 prepared the acid by reducing chloric acid with tartaric acid. G. Bruni and G. Levi used oxalic acid ... 

The preparation of chloric acid.—J. L. Gay Lussac10 prepared a soln. of chloric acid by treating barium chlorate with the proper quantity of sulphuric acid. 

Electrolytic processes for the perchlorates.—F. von Stadion found that if an aq. soln. of chlorine dioxide be included in Volta s circuit, at first very little gas is developed, but after some hours, oxygen and chlorine appear at the anode, and hydrogen at the cathode. The volume of hydrogen so obtained is nearly twice that of the oxygen. After some time the soln. is decolorized, and transformed into perchloric acid. In 1857, A. Riche 18 prepared perchloric acid by the electrolysis of hydrochloric acid, or of an aq. soln. of chlorine and ten years earlier, H. Kolbe prepared potassium perchlorate by the electrolysis of an aq. soln. of potassium chloride—acidified with sulphuric acid—and of potassium trichloro-methyl-sulphonate. H. Kolbe (1846), a pioneer in the electrolytic preparation of compounds, specially noted that the formation of perchloric acid is always preceded by that of chloric acid, and stated ... 

A very pure product and almost theoretical yield may be obtained by the oxidation of tellurium tetrachloride with chloric acid. A slight excess of chloric acid is used to avoid the formation of any explosive oxides of chlorine. The addition of concentrated nitric acid causes precipitation of the telluric acid, which may be freed from chlorine and nitrogen oxides by drying in a vacuum. Prepared by this method the acid has the composition H2Te04.2H2O.8... 

Alternatively, to reduce interference from any iron and tungsten present in the sample, the powdered plant material is boiled under reflux with 5.5 N hydrochloric acid. An ethonolic solution of 2% a-monoxime is added and a chloroform extract prepared. To the chloroform phase is added nitric acid per-chloric acid 3 1 v/v, and the mixture is heated until perchloric acid fumes are evolved. 

The halides of the palladium and platinum groups of metals closely resemble in character those of gold, which have already been described. The dihalides of the palladium group are all soluble, save Pdl2, which is prepared by precipitation with potassium iodide. Nitro-hydro-chloric acid yields the higher chloride it remains on evapo-... 

Owing to the fact that very few potassium salts are insoluble in water, it is not convenient to prepare chloric acid from the potassium salt for this purpose it is better to use the barium salt, made from baryta-water and chlorine a solution of this salt, when mixed with the equivalent amount of dilute sulphuric acid, yields a precipitate of barium sulphate, and chloric acid remains in solution. 

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... 

Chloric acid and its salts. This acid or its salts may be prepared by heating solutions of hypochlorous acid or hypochlorites ... 

Cupric chlorate, Cu(C108)2.—The chlorate is prepared by dissolving cupric hydroxide or carbonate in chloric acid, or by the interaction of cupric sulphate and barium chlorate. On evaporation of the solution it separates in the form of the tetrahydrate, which melts and decomposes at 73° C.13... 

Several 1,2, cyclopropanes containing a xtetone group nave been prepared by the elimination of hyaro-chloric acid from ( ertain y-chlorjiietoneB Thus methi lcyclopropane-2-acetyl, metnylcyclopropane-2-ben-zoyl and cyclopropane tolyl xetone have been made but tneir reactions have not been studied. 

Halogenated pyridazinones have been thus prepared from muco-chloric acid (35) 286,312-316 mucobromic acid, or the related chlorobromo acid. Instead of hydrazine semicarbazide can be used and the intermediate semicarbazone cyclized in hot acetic acid, loss of the carbamide group taking place simultaneously. Acid hydrazides likewise form hydrazones first, which cyclize with the aid of phosphorus oxychloride. Tosylhydrazones are reported to cyclize easily. ... 

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