What is the coordination number of the central metal ion in the complex Na₂[V(C₂O₄)₃]?

• A. 6
• B. 3
• C. 8
• D. 4

Answer: (A)

Verified step by step guidance

1. Identify the central metal ion in the complex. In Na₂[V(C₂O₄)₃], the central metal ion is V, which stands for vanadium.
2. Determine the ligands attached to the central metal ion. In this complex, the ligand is the oxalate ion, \( \text{C}_2\text{O}_4^{2-} \).
3. Count the number of oxalate ligands attached to the vanadium ion. The formula indicates there are three oxalate ions \( (\text{C}_2\text{O}_4) \) attached to vanadium.
4. Understand that each oxalate ion is a bidentate ligand, meaning it can form two bonds with the central metal ion. Therefore, each \( \text{C}_2\text{O}_4^{2-} \) contributes two coordination sites.
5. Calculate the coordination number by multiplying the number of oxalate ligands by the number of bonds each can form: \( 3 \text{ ligands} \times 2 \text{ bonds per ligand} = 6 \). Thus, the coordination number of vanadium in this complex is 6.