Identify a ligand having two donor atoms but uses a pair of electrons of either donor atom to form coordinate bond.

Step-by-step solution

NO ₂⁻ (nitrite) is an ambidentate ligand which has two donor atoms, N and O , but uses either of them to form a coordinate bond. It is termed as 'nitro'(for N-bonded ligand) and 'nitrito' (for O-bonded ligand)