Question

Which one of the following can show optical isomerism?

• A. $FeSO_{4}.7H_{2}O$
• B. $K _{3}\left[ Cr \left( C _{2} O _{4}\right)_{3}\right]$
• C. $K _{3}\left[ Fe ( CN )_{6}\right]$
• D. $\operatorname{Cr}\left[\left( NH _{3}\right)_{6}\right] Cl _{3}$

Answer 1

Answer: (B)

The anion of the compound $B$ is $\left[ Cr \left( C _{2} O _{4}\right)_{3}\right]^{3-}$ or $\left[ Cr ( Ox )_{3}\right]^{3-}$, where $Ox \equiv C _{2} O _{4}^{2-} .$ Since such octahedral . Since such octahedral complexes have non-super-imposable mirror images, so they show optical isomerism.