question_answer 8)

Explain [Co(NH3)6]3+ is an inner orbital complex whereas is an outer orbital complex.  

Answer:

In [Co(NH3)6]3+ Co is in +3 state and has configuration 3d6. In the presence of NH3, 3d electrons pair up leaving two d-orbitals empty. Hence, the hybridization is d2sp3 forming and inner orbital complex. In [Ni(NH3)6]2+, Ni is in +2 state and has configuration 3d8. In presence of NH3, the 3d electrons do not pair up. The hybridization is sp3d2 forming an outer orbital complex.