Among the following species
N₂, N₂⁺, N₂⁻, N₂²⁻, O₂, O₂⁺, O₂⁻, O₂²⁻
the number of species showing diamagnetism is
N₂, N₂⁺, N₂⁻, N₂²⁻, O₂, O₂⁺, O₂⁻, O₂²⁻
the number of species showing diamagnetism is
Answer: 2
Solution
A species is diamagnetic if all its electrons are paired (no unpaired electrons). Using molecular orbital theory:
Therefore, only N₂ and O₂²⁻ are diamagnetic. Answer: 2
- N₂: Bond order 3, all electrons paired → diamagnetic
- N₂⁺: One electron removed from bonding π orbital → 1 unpaired → paramagnetic
- N₂⁻: One electron added to antibonding π* orbital → 1 unpaired → paramagnetic
- N₂²⁻: Two electrons added to antibonding π* orbitals → 2 unpaired → paramagnetic
- O₂: Bond order 2, two unpaired electrons in π* orbitals → paramagnetic
- O₂⁺: One electron removed from π* → 1 unpaired → paramagnetic
- O₂⁻: One electron added to π* → 1 unpaired → paramagnetic
- O₂²⁻: Both π* orbitals filled, all paired → diamagnetic
Therefore, only N₂ and O₂²⁻ are diamagnetic. Answer: 2
JEE Main · 2022 · 25 Jul 2022 · Shift 1 · Integer answer