A solution containing Pb2+ and a solution containing IO3- are poured together and quickly mixed. After mixing, the solution contains 0.0030 M Pb2+ and 0.040 M IO3-. Immediately Pb(IO3)2(s), which has Ksp=2.510-13, begins to precipitate. Calculate the free concentrations of Pb2+ and IO3- after the precipitation reaction comes to equilibrium.

1 answer

Do the following:
Write the equation and balance it.
Calculate moles Pb^2+ and IO3^-
I expect one is a limiting reagent; determine which and how much of the Pb(IO3)2 will ppt.
Determine which reagent is in excess and how much excess.
Use Ksp, along with the excess common ion, to determine the solubility of Pb(IO3)2 in the solution.
Determine the concn of each ion from that.