Question

Among the following, which are ambidentate ligands?
(i) $SCN^{-}$
(ii) $NO^{-}_{3}$
(iii) $NO^{-}_{2}$
(iv) $C_{2}O^{2-}_{4}$

• A. (i) and (iii)
• B. (i) and (iv)
• C. (ii) and (iii)
• D. (ii) and (iv)

Answer 1

Answer: (A)

Ambidentate ligand has two or more donor atoms, but during complex formation, only one donor atom is attached to central metal.
$SCN^-$ ion has donor atoms $N$ and $S$.
It links to metal as either $M - SCN$ or $M - NCS$ .
$NO _{2}^{-}$group has donor atoms $N$ and $O$.
It links to metal as either $M - ONO$ or $M - NO _{2}$.