Question

Which of the following will show optical isomers?
(I) $Cis-\left[Co\right(N{H}_3{)}_2(en{)}_2{]}^{3+}$ (II) $Trans-\left[IrC{l}_2\right(C_2{O}_4{)}_2{]}^{3-}$ (III) $\left[Rh\right(en{)}_3{]}^{3+}$ (IV) $cis-\left[Ir\right(H_{2}O{)}_{3}C{l}_3]$.

• A. I, III only correct
• B. II, IV only correct
• C. I, III, IV only correct
• D. III only correct

Answer 1

Answer: (A)

I, III only correct

(i) $cis-\left[Co\right(N{H}_3{)}_2(en{)}_2{]}^{3+}$ contains no element of symmetry and is optically active. It has d and l forms.
(ii) $trans-\left[IrC{l}_2\right(C_2{O}_4{)}_2{]}^{3-}$ contains a plane of symmetry and is optically inactive.
(iii) $\left[Rh\right(en{)}_3{]}^{3+}$ contains no element of symmetry and is optically active. It has d and l forms.
(iv) $cis-\left[Ir\right(H_{2}O{)}_{3}C{l}_3]$ contains symmetry elements and is optically active.