Question

In which of the following complex ion, the central matal ion is in a state of $s{p}^3{d}^2$ hvbridisation?

• A. ${\left[CO{F}_6\right]}^{3-}$
• B. ${\left[Co{\left(N{H}_3\right)}_6\right]}^{3+}$
• C. ${\left[Fe(CN{)}_6\right]}^{3-}$
• D. ${\left[Cr{\left(N{H}_3\right)}_6\right]}^{3+}$

Answer 1

Answer: (A)

$F^{-}$is a weak ligand. It cannot pair up $d$-electrons and forms outer orbital octahedral complex.
$N{H}_3$ and $C{N}^{-}$are strong ligands. So, they pair up $d$-electrons and form their inner orbital complex.