Gold trichloride acid

Formula HAuCh MW 339.81 exists as tetrahydrate, HAuCh 4H20 MW 411.85 Synonyms chloroauric acid aurochlorohydric acid hydrochloroauric acid gold trichloride acid hydrogen tetrachloroaurate(lll). 

Synonyms Aurochlorohydric acid, Chlorauric acid, Gold trichloride (acid). 

Gold trichloride acid chloroauric acid aurochlorohydric acid hydrochloroauric acid. 

Daniel (Ref 1) stated that Vor fulminant deposits as a chamois (clear yel) powder on tteating gold trichloride with ammonia. The same method is listed by Davis on p 401, who also says that the method of prepn by Basil. Valentin succeeded because the sal ammoniac used for the prepn of the aqua regia supplied the necessary ammonia. If gold is dissolved in aqua regia prepd from nitric acid and common salt, and if. the soln is treated with K carbonate, the resulting ppt is not expl. FG loses its expl props if it is allowed to stand in contact with sulfur... 

Platinum(II)15 and palladium(II)16 complexes of phosphorus trichloride undergo solvolysis in water and alcohols to form complexes with orthophosphorous acid or orthophosphite ligands (equation 6). Similar reactions occur between the palladium(II) phenyldichlorophosphine complex (8) and the diols ethyleneglycol and catechol, but new chelate rings are not formed (Scheme 2). Solvolysis also occurs with attack of diphenylphosphinic acid or a similar diphenylchlorophosphine complex (9) (equation 7). The palladium complexes (8) and (9) are unstable to excess methanol, water or base and undergo reduction. Similarly, the phosphorus trichloride gold(I) complex (10) is reduced by water, but forms stable products on reaction with alcohols (equation 8).15 During the above reactions, the phosphorus—metal bond remains intact and the overall process is one of substitution at phosphorus. 

Red phosphorus is less soluble than white in all solvents. In water and alcohol it is almost insoluble. It is somewhat soluble in ether and in hot acetic acid, from which it is reprecipitated by water. It is slightly soluble in phosphorus trichloride. These solubilities refer to the ordinary preparation, which, as shown on p. 32, usually contains residual quantities of the white form. Red phosphorus is able to reduce salts, especially those of the noble metals, in aqueous solution on boiling. Salts of mercury are reduced to the metal those of gold and silver give insoluble phosphides while ferric and stannic salts are reduced to ferrous and stannous respectively.5... 

In 1850 Levol6 converted a weighed quantity of gold into the trichloride, reduced this derivative with sulphurous acid, precipitated as barium sulphate the sulphuric acid formed, and weighed the precipitate. The mean of two values for the ratio 2Au 3BaS04 leads to Au = 196 49. 

Another preparation is made by dissolving one gram-molecule of Salvarsan, one gram-molecule of freshly prepared silver halide and one gram-molecule of antimony trichloride in water, by the aid of heat, then adding a concentrated solution of citric acid, followed by a dilute solution of sulphuric acid to precipitate the base. The silver salt may be replaced by salts of gold, platinum, or copper. ... 

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