Question

Identify the type of isomerism exhibited by the following complexes:
(i) [Co(NH₃)₅NO₂]²⁺
(ii) [Co(en)₃]³⁺Cl₃

Hint:

Linkage isomerism occurs when a ligand can coordinate to the metal through two different atoms, while optical isomerism occurs when a molecule lacks any symmetry elements, such as a plane of symmetry, making it non-superimposable on its mirror image.

Answer 1

 (i) \( [\text{Co(NH}_3\text{)}_5\text{NO}_2]^{2+} \) exhibits linkage isomerism, as the NO₂ ligand can bind through either the nitrogen or the oxygen atom. 
 (ii) \( [\text{Co(en)}_3]\text{Cl}_3 \) exhibits optical isomerism, as the complex is chiral and does not have a plane of symmetry.