question_answer

Which one of the following complexes is an outer orbital complex? (At. nos.\[Mn=22,Fe=26,Co=27,Ni=28\])

A) \[{{[Fe{{(CN)}_{6}}]}^{4-}}\]     

B)       \[{{[Mn{{(CN)}_{6}}]}^{4-}}\]                    

C)  \[{{[Co{{(N{{H}_{3}})}_{6}}]}^{3+}}\]    

D)        \[{{[Ni{{(N{{H}_{3}})}_{6}}]}^{2+}}\]

Correct Answer: D

Solution :

Complexes which use one ns, three np and two nd-orbital to form the sixhybrids are called outer-orbital complexes. So, find the electronic configuration of central metal ion. In this case alsois a strong ligand but electrons remain unpaired since only one orbital is left vacant in 3d. Thus