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7700631 
Journal Article 
An investigation of the lead(II)-hydroxide system 
Perera, WN; Hefter, G; Sipos, PM; , 
2001 
Yes 
Inorganic Chemistry
ISSN: 0020-1669
EISSN: 1520-510X 
40 
16 
3974-3978 
English 
11466056 
A detailed investigation of the Pb(II)/OH(-) system has been made in NaClO(4) media at 25 degrees C. Combined UV-vis spectrophotometric-potentiometric titrations at [Pb(II)](T) < or = 10 microM using a long path length cell detected only four mononuclear hydroxide complexes. The values of log beta(1)(q)(), for the equilibria Pb(2+)(aq) + qH(2)O <--> Pb(OH)(q)()((2)(-)(q)()()+)(aq) + qH(+)(aq), were -7.2, -16.1, -26.5, and -38.0 for q = 1-4, respectively, at ionic strength I = 1 M (NaClO(4)). Similar results were obtained at I = 5 M (NaClO(4)). No evidence was found for higher order complexes (q > 4) even at very high [OH(-)]/[Pb(II)] ratios, nor for polynuclear species at [Pb(II)](T) < or = 10 microM. Measurements using (207)Pb-NMR and Raman spectroscopies and differential pulse polarography (DPP) provided only semiquantitative confirmation. The mononuclear Pb(OH)(q)()((2)(-)(q)()()+)(aq) complexes are the only hydrolyzed species likely to be significant under typical environmental and biological conditions.