Which complex has the highest crystal field splitting energy (Δo) with Co₃+ as the central ion?
Δo depends on ligand strength (spectrochemical series: CN− > NH₃ > H₂O > F−). [Co(CN)6]3− with strong field CN− has the highest Δo.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Crystal Field Theory - CFT and Crystal Field Splitting and CFSE