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Answer the following.
[Co(NH₃)₆]³⁺ is an inner orbital complex whereas [CoF₆]³⁻ is an outer orbital complex. Why? (Given…
$[\text{Co}(\text{NH}_3)_6]^{3+}$ is an inner orbital complex whereas $[\text{CoF}_6]^{3-}$ is an outer orbital complex. Why? (Given: Atomic number of $\text{Co} = 27$).
Answer
Answer
Because $\mathrm{NH_3}$ is a strong field ligand, it pairs up the $3d$ electrons of $\mathrm{Co^{3+}}$ ($3d^6$) and two inner $3d$ orbitals are used ($\mathrm{d^2sp^3}$, inner orbital). $\mathrm{F^-}$ is a weak field ligand, it cannot pair the electrons, so outer $4d$ orbitals are used ($\mathrm{sp^3d^2}$, outer orbital).