A compound MX₂ has observed and normal molar masses 65.6 and 164 respectively. Calculate the apparent degree of ionization of MX₂

$$\begin{gathered} \mathrm{i}=\frac{\mathrm{Normal} \mathrm{molar} \mathrm{mass}}{\mathrm{Observed} \mathrm{molar} \mathrm{mass}}=\frac{164}{65.6}=2.5 \\ \mathrm{\alpha }=\frac{\mathrm{i}-1}{\mathrm{n}-1} \\ \mathrm{n}=3(\mathrm{number} \mathrm{of} \mathrm{ions}) \\ \mathrm{\alpha }=\frac{2.5-1}{3-1}-\frac{1.5}{2}=0.75 \end{gathered}$$
So percentage ionization of MX₂ will be 75%.