Question

Which of the following complex ion possesses sp $^{3} d ^{2}$ hybridization?

• A. $\left[ Cr \left( NO _{2}\right)_{6}\right]^{3-}$
• B. $\left[ Fe ( CN )_{6}\right]^{4-}$
• C. $\left[ FeF _{6}\right]^{3-}$
• D. $\left[ Ni ( CO )_{4}\right]$

Answer 1

Answer: (C)

$\left[ FeF _{6}\right]^{3-}$ complex ion possesses sp $^{3} d ^{2}$ hybridization.
The electronic configurations of $Cr , Fe, Co$ and $Ti$ in the complexes are
$(3 d )^{3},(3 d )^{5},(3 d )^{6}$ and $(3 d )^{1}$, respectively.
These involve $d ^{2} sp ^{3}, sp ^{3} d ^{2}, d ^{2} sp ^{3}$ and $d ^{2} sp ^{3}$ hybridization respectively.