Gold halide complexes solubility

Mercury (Hg, at. mass 200.59) occurs in its compounds in the I and II oxidation states. Mercury(II) is similar in its chemical properties to copper(II) and lead (II), whereas mercury(I) resembles silver and gold(I). Mercury(II) forms stable, mostly water-soluble, halide complexes. 

Rubidium metal alloys with the other alkali metals, the alkaline-earth metals, antimony, bismuth, gold, and mercury. Rubidium forms double halide salts with antimony, bismuth, cadmium, cobalt, copper, iron, lead, manganese, mercury, nickel, thorium, and zinc. These complexes are generally water insoluble and not hygroscopic. The soluble rubidium compounds are acetate, bromide, carbonate, chloride, chromate, fluoride, formate, hydroxide, iodide,... 

Gold Ions.—The metal forms univalent and tervalent ions characterized by their low electroaffinity. This property finds expression in the formation of complex derivatives with most anions, in the comparatively low solubility of the halides and oxides, and in the hydrolytic decomposition of its salts. 

Ammonia complexes.. EflFect of complex formation on solubility. Cyanide complexes. The cyanide process of treating gold and silver ores. Complex halides and other complexes. Sodium thiosulfate as photographic fixer. Hydroxide complexes. Amphoteric hydroxides. Sulfide complexes. Equilibrium expressions for complex formation. Structural chemistry—tetrahedral, octahedral, square complexes. Existence of isomers. 

The complex ions [AuCb] and [AuBrj]" disproportionate in aqueous solution according to equation (6) for L = Cl or Br , but [Aula]" does not. However, the complex ions are stabilized in the presence of excess halide, and calculations indicate that soluble gold in sea water is present as ions such as [AuCla]", [AuCLBrl" and [AuCl(OH)]". 

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