What concentration of the lead ion, Pb^{2+} , must be exceeded to precipitate PbCl2 from a solution that is 1.00 x 10^{-2} M in the chloride ion, Cl^- ? Ksp for lead chloride is 1.17×10−5 .

Answer 1

Ksp = (Pb^2+)(Cl^-)^2
Substitute for Ksp and (Cl^-) and solve for (Pb^2+)