Chapter 4, Problem 151AP

The concentration of ${\text{Cu}}^{\text{2+}}$ ions in the water (which also contains sulfate ions) discharged from a certain industrial plant is determined by adding excess sodium sulfide $\left({\text{Na}}_{\text{2}}\text{S}\right)$ solution to 0.800 L of the water. The molecular equation is

${\text{Na}}_{\text{2}}\text{S}\left(aq\right)+{\text{CuSO}}_{\text{4}}\left(aq\right)\to {\text{Na}}_{\text{2}}{\text{SO}}_{\text{4}}\left(aq\right)+\text{CuS}\left(s\right)$

Write the net ionic equation and calculate the molar concentration of ${\text{Cu}}^{\text{2+}}$ in the water sample if 0.0177 g of solid CuS is formed.