Question

A cell is set up as shown in the figure. It is observed that EMF of the cell comes out to be $2.36$V. Which of the given statements is not correct about the cell?

• A. Reduction takes place at magnesium electrode and oxidation at SHE
• B. Oxidation takes place at magnesium electrode and reduction at SHE
• C. Standard electrode potential for $M{g}^{2+}|Mg$ will be $-2.36$V
• D. Electrons flow from magnesium electrode to hydrogen electrode

Answer 1

Answer: (B)

Oxidation takes place at magnesium electrode and reduction at SHE

Oxidation takes place as an anode.

Reduction takes place at a cathode.

$\therefore$ Oxidation $Mg⟶M{g}^{2+}+2e^{-}$

Reduction $2H^{+}+2e^{-}⟶H_2$

Hence, $E_{cell}=+ve$ as $Mg$ is more reactive than hydrogen.

Hence, oxidation at $Mg$ electrode, reduction at SHE.

Hence option (B) is correct.