Question

Arrange the following ligands in their increasing d-orbital splitting: (A) NH\(_3\)
(B) C\(_2\)O\(_4^{2-}\)
(C) OH\(^-\)
(D) CN\(^-\)

• A. (A), (B), (C), (D)
• B. (A), (C), (B), (D)
• C. (B), (A), (D), (C)
• D. (C), (B), (A), (D)

Hint:

Strong field ligands like CN\(^-\) and CO cause large d-orbital splitting, while weak field ligands like OH\(^-\) cause small splitting.

Answer 1

The Correct Option is D

Step 1: Understanding Ligand Field Strength.
The strength of the ligand field influences the d-orbital splitting in transition metal complexes. Strong field ligands cause a large splitting of the d-orbitals, while weak field ligands cause a smaller splitting. The ligand field strength follows the trend: \[ \text{CN}^- > \text{CO}_4^{2-} > \text{NH}_3 > \text{OH}^- \]

Step 2: Analyzing the Ligands.
- (A) NH\(_3\) is a weak field ligand. - (B) C\(_2\)O\(_4^{2-}\) (oxalate) is a moderate field ligand. - (C) OH\(^-\) is a weaker field ligand compared to NH\(_3\). - (D) CN\(^-\) is a strong field ligand, causing the largest splitting.

Step 3: Conclusion.
Thus, the order of increasing d-orbital splitting is: \[ \text{OH}^- < \text{C}_2\text{O}_4^{2-} < \text{NH}_3 < \text{CN}^- \] So, the correct answer is option (4): (C), (B), (A), (D).