question_answer

In which of the following complex ion, the central metal ion is in a state of \[s{{p}^{3}}{{d}^{2}}\]hybridisation?

A)                  \[{{[Co{{F}_{6}}]}^{3-}}\]            

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

C)  \[{{[Fe{{(CN)}_{6}}]}^{3-}}\]     

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

Correct Answer: A

Solution :

Electronic configuration of \[C{{O}^{2+}}\] ion                 \[{{F}^{-}}\] is a weak ligand. It cannot pair up electrons with d-subshell and forms outer orbital octahedral complex. \[{{[Co{{(N{{H}_{3}})}_{6}}]}^{3+}}\] ion                 \[N{{H}_{3}}\] and \[C{{N}^{-}}\] are strong ligands. So, they form inner orbital complex.