Chapter 3, Problem 141AP

An impure sample of zinc (Zn) is treated with an excess of sulfuric acid $\left({\text{H}}_{\text{2}}{\text{SO}}_{\text{4}}\right)$ to form zinc sulfate $\left({\text{ZnSO}}_{\text{4}}\right)$ and molecular hydrogen $\left({\text{H}}_{\text{2}}\right)$. (a) Write a balanced equation for the reaction. (b) If 0.0764 g of ${\text{H}}_{\text{2}}$ is obtained from 3.86 g of the sample, calculate the percent purity of the sample. (c) What assumptions must you make in part (b)?