Which of the following molecule or ions is a bidentate ligand?

• Correct answer
  A

  $\mathrm{C}_2 \mathrm{O}_4^{2-}$
• B

  $\mathrm{Br}_2^{+}$
• C

  $\mathrm{CH}_3 \mathrm{NH}_2$
• D

  $\mathrm{CH}_3-\mathrm{C} \equiv \mathrm{N}$

Solution

Bidentate ligands are those ligand which can coordinate to metal atom by two donor atoms. e.g.

Hence, the correct answer is option: 'A'.