Question

Calculate the formula unit mass of ${\mathrm{CaCl}}_2$.

Answer 1

$$\begin{gathered} \mathrm{Formula}\mathrm{unit}\mathrm{mass}\mathrm{of}{\mathrm{CaCl}}_2=\mathrm{Atomic}\mathrm{mass}\mathrm{of}\mathrm{Ca}+(2\times \mathrm{Atomic}\mathrm{mass}\mathrm{of}\mathrm{Cl}) \\ =40+2\times 35.5 \\ =40+71 \\ =111\mathrm{u} \end{gathered}$$

Therefore,the formula unit mass of ${\mathrm{CaCl}}_2$ is 111u.