Use the solubility-product constant for Cr (OH) 3 (
Ksp = 6.7×10?31) and the formation constant for
Cr (OH) ?4 from the following table to determine the concentration
of Cr (OH) ?4 in a solution that is buffered at pH= 11 and is in
equilibrium with solid Cr (OH) 3.
Table Formation Constants for Some Metal Complex Ions in Water at
25 ?C
Complex Ion
Kf
Equilibrium Equation
Ag(NH3)+2
1.7×107
Ag+(aq)+2NH3(aq)?Ag(NH3)+2(aq)
Ag(CN)?2
1×1021
Ag+(aq)+2CN?(aq)?Ag(CN)?2(aq)
Ag(S2O3)3?2
2.9×1013
Ag+(aq)+2S2O2?3(aq)?Ag(S2O3)3?2(aq)
CdBr2?4
5×103
Cd2+(aq)+4Br?(aq)?CdBr2?4(aq)...