The degree of ionization ($\alpha$) of a weak electrolyte is the ratio of its molar conductance at a given concentration ($\Lambda_m^c$) to its molar conductance at infinite dilution ($\Lambda_m^\circ$). $\alpha = \frac{\Lambda_m^c}{\Lambda_m^\circ}$ Given: Molar conductance at given concentration, $\Lambda_m^c = 9.54 \text{ ohm}^{-1}\text{cm}^2\text{mol}^{-1}$ Molar conductance at infinite dilution, $\Lambda_m^\circ = 238 \text{ ohm}^{-1}\text{cm}^2\text{mol}^{-1}$ $\alpha = \frac{9.54}{238} = 0.04008$ Percentage degree of ionization = $\alpha \times 100 = 0.04008 \times 100 = 4.008\%$.