Decreasing order of stability of O₂ , O₂⁻ , O₂⁺ and O₂²⁻ is

Options

(a) O₂²⁻ > O₂⁻ > O₂ >O₂⁺
(b) O₂> O₂⁺ > O₂²⁻ > O₂⁻
(c) O₂⁻ > O₂²⁻ > O₂⁺ >O₂
(d) O₂⁺ > O₂ > O₂⁻ > O₂²⁻

Correct Answer:

O₂⁺ > O₂ > O₂⁻ > O₂²⁻

Explanation:

According to molecular orbital theory as bond order decreases stability of the molecule decreases
Bond order =1/2 (N(b)-N(a))
Bond order for O₂⁺=1/2 (10-5)=2.5
Bond order for O₂=1/2 (10-6)=2
Bond order for O₂⁻=1/2 (10-7)=1.5
Bond order for O₂²⁻=1/2 (10-8)=1.0
hence the correct order is
O₂⁺ > O₂ > O₂⁻> O₂²⁻