The equivalent conductances of two strong electrolytes at infinite dilution in $H_2O$ (where ions move freely through a solution) at $25^{\circ}C$ are given below : <br> $\bigwedge^{\circ}_{CH_3COONa }= 91.0\;S \;cm^2/equiv $ <br>$ \bigwedge^{\circ}_{HCl} = 426.2 \; S\;cm^2/equiv$ <br> What additional information/quantity one needs to calculate $\bigwedge^{\circ}$ of an aqueous solution of acetic acid ?