9.8     Explain [Co(NH_{3})_{6}]^{3+} is an inner orbital complex whereas [Ni(NH_{3})_{6}]^{2+} is an outer orbital complex.

Answers (1)
D Devendra Khairwa

Firstly consider  [Co(NH_{3})_{6}]^{3+}   :-   

    The oxidation state of cobalt is +3. So the electronic configuration of it will be d6.

Since (NH3) is a strong ligand so the pairing of electron will be there. 


So, it has d2sp3 hybridisation and an inner orbital complex.


Now consider,[Ni(NH_{3})_{6}]^{2+}

    The oxidation state of nickel is +3. So its electronic configuration will be d8.

Also (NH3) is a strong ligand so pairing of electrons will be seen.


Thus     [Ni(NH_{3})_{6}]^{2+} is an outer orbital complex.