Chapter 16, Problem 148E

An analytical procedure for finding the chloride ion concentration in a solution involves the precipitation of silver chloride: ${\text{Ag}}^{+}+{\text{Cl}}^{-}\to \text{AgCl}$. What is the molarity of the chloride ion if $16.80\text{mL}$ of $0.629\text{M}$ silver nitrate (the source of silver ion) is needed to precipitate all of the chloride ion in a $25.00\text{-mL}$ sample of the unknown?

Silver nitrate solution is added to an unknown chloride-ion solution, yielding a precipitate of silver chloride.