Question

The coordination number and the oxidation state of the element ‘E’ in the complex [E(en)₂(C₂O₄)]NO₂ (where (en) is ethylenediamine) are, respectively ______.

Options

• 6 and 2

• 4 and 2

• 4 and 3

• 6 and 3

Answer 1

The coordination number and the oxidation state of the element ‘E’ in the complex [E(en)₂(C₂O₄)]NO₂ (where (en) is ethylenediamine) are, respectively 6 and 3.

Explanation:

• Ethylenediamine (en) and oxalate (C₂O₄) are bidentate ligands, contributing 4 and 2 coordination sites, respectively. Therefore, the coordination number is 6.
• NO₂ is a neutral counterion, and the ligands are neutral, so the oxidation state of E is +3 to balance the charge.