Chapter 12, Problem 12.94PAE

You are designing a process to remove carbonate ions from an aqueous system by precipitation. If the effectiveness of the process is the only concern (meaning there are no environmental or other issues involved), which of the following metal ions would be the best choice: ${\text{Ca}}^{\text{2+}}{\text{,Fe}}^{\text{2+}}{\text{,Pb}}^{\text{2+}}\text{,}\text{or}{\text{Ag}}^{\text{2+}}$ ? Explain your answer.

Salt	$K_{\text{sp}}$
${\text{CaCO}}_3$	$4.8\times {10}^{-9}$
${\text{FeCO}}_3$	$3.5\times {10}^{-11}$
${\text{PbCO}}_3$	$1.5\times {10}^{-13}$
${\text{Ag}}_2{\text{CO}}_3$	$8.2\times {10}^{-12}$