Gold , tetrachloro

Tetrabutylammonium tetrachloro-iodate(III), 5 176 Tetrach]oroauric(III) acid, and its reduction to gold with hydro-. quinone, 4 14, 15 Tetrachloro (diethylene)diplatinum-(II), 6 210... 

One example is the square-planar tetrachloro- and tetrabromo-complexes formed by gold(III) in aqueous solution, which can be uniquely and precisely structure determined from a single diffraction curve (18). The heavy atoms in the complexes and the highly concentrated solutions, that can be prepared, result in dominant contributions from the complexes to the scattering curve. 

Gold(III) chloride (0 33m for gold). Dissolve 13 3 g sodium tetrachloro-aurate(III) dihydrate, NaAuCl4.2H20, in water and dilute to 100 ml. Alternatively, dissolve 6 57 g gold metal in 50 ml aqua regia, evaporate the solution to dryness, and dissolve the residue in 100 ml water. 

Gold is resistant to acids only aqua regia dissolves it when tetrachloro-aurate(III), [AuC ]", anions are formed. Gold dissolves slowly in potassium cyanide, when dicyanoaurate(I), [Au(CN)2] , anions are formed. From both the monovalent and trivalent forms gold can easily be reduced to the metal. Gold(I) compounds are less stable than those of gold(III). 

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