Question

Which of the following is a bidentate ligand?

• A. E.D.T.A
• B. Ethylene diamine
• C. Acetate ion
• D. Pyridine

Hint:

Bidentate ligands form more stable chelate complexes due to the chelate effect.

Answer 1

The Correct Option is B

Step 1: Understanding bidentate ligands.
Bidentate ligands contain two donor atoms which can attach to a central metal ion, forming two coordinate bonds simultaneously.
Step 2: Analysis of options.
(A) E.D.T.A: This is a hexadentate ligand (can donate six pairs of electrons), not just bidentate.
(B) Ethylene diamine: Correct — It has two $-NH_2$ groups, each donating a lone pair, making it bidentate.
(C) Acetate ion: Monodentate, binds through one oxygen atom.
(D) Pyridine: Monodentate, binds through nitrogen only.
Step 3: Conclusion.
Thus, the correct answer is (B) Ethylene diamine.