Appeared in: 2023 (3 sets)
(a) Which of the following species cannot act as a ligand ? Give reason. $\text{OH}^-$, $\text{NH}_4^+$, $\text{CH}_3\text{NH}_2$, $\text{H}_2\text{O}$
(b) The complex $[\text{Co}(\text{NH}_3)_5(\text{NO}_2)]\text{Cl}_2$ is red in colour. Give IUPAC name of its linkage isomer.