Question

why do Cu get oxidised from Cu--->Cu²⁺ and not Cu--->Cu⁺,
when Cu and Fe³⁺ are taken as electrodes .

Answer 1

Dear Student,

Electronic configuration of Cu = [Ar] 3d^​​10 4s¹
Electronic configuration of Cu⁺ = [Ar] 3d^​​10
Electronic configuration of Cu²⁺ = [Ar] 3d^​​9
3d¹⁰ is more stable than 3d⁹, yet in aqueous solutions, Cu²⁺ is more stable than Cu⁺. This is due to high hydration enthalpy of Cu²⁺. Therfore, Cu²⁺ is more stable than Cu⁺ and hence, Cu gets oxidised to Cu²⁺ than Cu⁺.


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