Question
Explain why:
(i) E° for Mn3+ / Mn2+ couple is more positive than that Fe3+/Fe2+. (At. No. Mn = 25, Fe = 26).
(ii) Ce3+ can be easily oxidised to Ce4+ (At. No. Ce= 58).
Solution
Answer:
(i) Mn2+ is more stable than Mn3+ because Mn+2 has exactly half-filled orbitals, while Fe+2 after losing one e– half-filled orbitals.
(ii) Ce+4 achieve inert gas structure of Xenon, to require extra stability.