\(9.65 \mathrm{C}\) of electric current is passed through fused anhydrous magnesium chloride. The magnesium metal thus, obtained is completely converted into a Grignard reagent. The number of moles of the Grignard reagent obtained is

\(\mathrm{MgCl}_{2} \longrightarrow \mathrm{Mg}^{2+}+2 \mathrm{Cl}^{-}\)
\(\mathrm{Mg}^{2+}+2 \mathrm{e}^{-} \longrightarrow \underset{1 \mathrm{~mol}}{\mathrm{Mg}}\) (at cathode)
\(\because 2 \mathrm{~F}(2 \times 96500 \mathrm{C}) \text { deposits } \mathrm{Mg}=1 \mathrm{~mol}\)
\(\therefore 9.65 \mathrm{C}(2 \times 96500 \mathrm{C}\) ) deposits \(\mathrm{Mg}=1 \mathrm{~mol}\)
\(=\frac{1 \times 9.65}{2 \times 96500}\)
\(=5 \times 10^{-5} \mathrm{~mol}\)
In order to prepare Grignard reagent, one mole of \(\mathrm{Mg}\) is used per mole of reagent obtained. Thus, by \(5 \times 10^{-5} \mathrm{~mol} \mathrm{Mg}, 5 \times 10^{-5}\) mole of Grignard reagent are obtained.