Which complex has a metal ion with a d7 configuration in an octahedral field that is high spin?
[Co(H₂O)6]2+ (Co₂+, d7) with weak field H₂O in an octahedral field is high spin (t2g5 eg2).
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Crystal Field Theory - CFT and Crystal Field Splitting and CFSE