What is the overall voltage for the nonspontaneous redox reaction involving Mg and Cu and their ions?
A. 0.34 + (-2.37)
B. -2.37 - 0.34
C. 2.37 - 0.34
D. 0.34 +2.37
SUBMIT

Answer D => E°(Mg°/Cu⁺²) = 0.34 + 2.37 = 2.71v

Explanation:

(Oxidation) =>  Mg°(s) => Mg⁺²(aq) + 2e⁻    E°(Mg°/Mg⁺²) = -2.37 v

(Reduction) => Cu⁺²(aq) + 2e⁻ => Cu°(s)     E°(Cu⁺²/Cu°) = +0.34 v

Net Rxn => Mg°(s) + Cu⁺²(aq) => Mg⁺²(aq) + Cu°(s)

Std Cell Potential (25°C/1Atm) = E°(Redn) = E°(Oxidn) = +0.34v - (-2.37v)

= 0.34v + 2.37v = 2.72v

it forms an anion that has a larger radius. anions have a negative charge and are larger than the original atom.