Question:
E° of Cu is + 0.34V while that of Zn is – 0.76V. Explain.
Solution:
The reduced form of Cu2+ is more stable than the oxidized form of Cu. Therefore, the value of E° is positive for Cu. Removing two electrons gives a stable configuration
[Ar]3d10 with filled orbitals. So, the oxidized form is more stable than the reduced form. Therefore, the value of E° is negative for Zn.