Question

Why are E\(^\circ\) values for Mn and Zn more negative than expected?

Hint:

Extra stability of half-filled and fully filled orbitals affects E° values.

Answer 1

For Mn:

• Mn\(^{2+}\) has stable half-filled \(3d^5\) configuration
• Reduction potential becomes more negative

For Zn:

• Zn\(^{2+}\) has fully filled \(3d^{10}\) configuration
• Greater stability → more negative reduction potential