Answer:
A. 2.71 V
Step-by-step explanation:
The standard reduction potential, E° of the metals are as follows:
Mg²⁺ + 2e⁻ ⇌ Mg; E° = -2.372
Cu²⁺ + 2e⁻ ⇌ Cu; E° = +0.337
Since magnesium has the the lower E°, it will serve as the anode in the electrolytic cell while copper will serve as the cathode.
At the anode; Mg ⇌ Mg²⁺ + 2e⁻, E° = -2.372
At the cathode; Cu²⁺ + 2e⁻ ⇌ Cu, E° = +0.337
EMF of the cell = E° cathode - E° anode = 0.337 - (-2.372) = 2.71 V
Therefore, EMF of the cell is 2.71 V