The Hydrolysis of AuCl 4 - and the Stability of Aquachlorohydroxocomplexes of Gold(III) in Aqueous Solution

The equilibria AuCl (4) (-) +jOH(-)+kH(2)Oa double dagger OE AuCl4-j-k (OH) (j) (H2O) (k) (k-1) +(j+k)Cl-, beta (jk) (0a parts per thousand currency signj,ka parts per thousand currency sign4) have been studied spectrophotometrically at 20 A degrees C in aqueous solution. For I=2 mola <...dm(-3)(HClO4) the conventional constants, beta (i) (*) , of the equilibria, Au-*+iCl(-) a double dagger OE AuCl (i) (*) , are equal to log (10) beta (1) (*) =(6.98 +/- 0.08); log (10) beta (2) (*) =(13.42 +/- 0.05); log (10) beta (3) (*) =(19.19 +/- 0.09); and log (10) beta (4) (*) =(24.49 +/- 0.07), where [AuCl (i) (*)]=a[AuCl (i) (OH) (j) (H2O)(4-i-j) ] at i=const. The hydrolysis and other transformations of AuCl (4) (-) in aqueous solution are discussed. On the basis of new and known data, a full set of equilibrium constants, beta (jk) , or their estimates has been obtained.