Haloalkanes and Haloarenes — Chemistry STD 12 Science — Question

Electrode potential for Mg electrode varies according to the equation

$\text{E}_{\text{Mg}^{2+}|\text{Mg}}=\text{E}^\ominus_{\text{Mg}^{2+}|\text{Mg}}-\frac{0.059}{2}\log\frac{1}{\big[\text{Mg}^{2+}\big]}$ The graph of $\text{E}_{\text{Mg}^{2+}|\text{Mg}}\text{ vs }\log\big[\text{Mg}^{2+}\big]\text{ is}:$