NEETChemistryCoordination Compounds
Consider the following octahedral complexes: (I) [ Fe ( H ₂ O )₆]³⁺ (II) [ Fe ( CN )₆]³⁻ (III) [ Co ( C ₂ O ₄)₃]³⁻ (IV) [ CoF ₆]³⁻ The correct sequence of their hybridization states is:
Options
- Asp^3d^2 , d^2sp^3 , d^2sp^3 , sp^3d^2
- Bsp^3d^2 , d^2sp^3 , sp^3d^2 , sp^3d^2
- Cd^2sp^3 , d^2sp^3 , d^2sp^3 , sp^3d^2
- Dsp^3d^2 , sp^3d^2 , d^2sp^3 , sp^3d^2
Correct answer
A. sp^3d^2 , d^2sp^3 , d^2sp^3 , sp^3d^2
Step-by-step solution
(I) In [ Fe ( H ₂ O )₆]³⁺ , Fe is in +3 oxidation state ( 3d^5 ). H ₂ O is a weak field ligand, so no pairing occurs. It forms an outer orbital complex with sp^3d^2 hybridization. (II) In [ Fe ( CN )₆]³⁻ , Fe is in +3 oxidation state ( 3d^5 ). CN ^- is a strong field ligand, causing pairing of electrons. It forms an inner orbital complex with d^2sp^3 hybridization. (III) In [ Co ( C ₂ O ₄)₃]³⁻ , Co is in +3 oxidation state ( 3d^6 ). Oxalate ( C ₂ O ₄²⁻ ) acts as a strong field ligand for Co(III), causing electron p