Question

Which of the following will show optical activity?

• A. $K_2\left[PtBrClFI\right]$
• B. $\left[Cr\right(en{)}_3]C{l}_3$
• C. $\left[Co\right(N{H}_3{)}_4\left(Cl{)}_2\right]N{O}_3$
• D. $\left[Fe\right(N{H}_3{)}_3\left(Cl{)}_3\right]$

Answer 1

The correct option is B $\left[Cr\right(en{)}_3]C{l}_3$

(a) $K_2\left[PtBrClFI\right]$ is square planar complex and will be optically inactive.

(b) $\left[Cr\right(en{)}_3]C{l}_3$ will be optically active.


(c) $\left[Co\right(N{H}_3{)}_4\left(Cl{)}_2\right]N{O}_3$ exists in two isomeric forms where both are optically inactive due to the presence of a plane of symmetry.
(d) $\left[Fe\right(N{H}_3{)}_3\left(Cl{)}_3\right]$ exists in two isomeric forms where both are optically inactive due to the presence of a plane of symmetry.