Question

The order of energy absorbed which is responsible for the order of complexes:

1. [Ni(H₂O)₂(en)]²⁺
2. [Ni(H₂O)₄(en)]²⁺ and
3. [Ni(en)₃]²⁺

विकल्प

• (C) > (B) > (A)

• (C) > (A) > (B)

• (B) > (A) > (C)

• (A) > (B) > (C)

Answer 1

(C) > (A) > (B)

Explanation:

The order of energy absorbed depends on ligand field strength. Stronger field ligands cause more d-orbital splitting and higher energy absorption.

• [Ni(en)₃]²⁺ (strongest ligand field, highest energy absorbed)
• [Ni(H₂O)₂(en)]²⁺ (mix of strong and weak ligands, moderate energy absorbed)
• [Ni(H₂O)₄(en)]²⁺ (mostly weak water ligands, lowest energy absorbed)

Order of energy absorbed: [Ni(en)₃]²⁺ > [Ni(H₂O)₂(en)]²⁺ > [Ni(H₂O)₄(en)]²⁺