JEE Main · 2023 · 01 Feb 2023 · Shift 2 · Coordination Compounds

Two isomers arise when a complex contains an ambidentate ligand that can bind through either of two different donor atoms. The nitrite ligand in $[\mathrm{Co}(\mathrm{N}{\mathrm{H}}_3{)}_5\mathrm{N}{\mathrm{O}}_2{]}^{2+}$ can coordinate through nitrogen to give the nitro form or through oxygen to give the nitrito form, producing a pair of linkage isomers. The aqua and chloro complexes contain only ligands with a single donor atom and so exist in one form each. The cation showing two isomers is $[\mathrm{Co}(\mathrm{N}{\mathrm{H}}_3{)}_5\mathrm{N}{\mathrm{O}}_2{]}^{2+}$.