Easy MCQ +4 / -1 PYQ · JEE Mains 2021

The bond order and magnetic behaviour of $O_2^ -$ ion are respectively :

  1. A 1.5 and paramagnetic Correct answer
  2. B 1.5 and diamagnetic
  3. C 2 and diamagnetic
  4. D 1 and paramagnetic

Solution

$$O_2^ - = {({\sigma _{1s}})^2}{(\sigma _{1s}^*)^2}{({\sigma _{2s}})^2}{(\sigma _{2s}^*)^2}{({\sigma _{2{p_z}}})^2}$$$$\left( {\pi _{2{p_x}}^2 = \pi _{2{p_y}}^2} \right)\left( {\pi _{2{p_x}}^{*2} = \pi _{2{p_y}}^{*1}} \right)$$<br><br>Bond order = ${{10 - 7} \over 2} = 1.5$ <br><br>and paramagnetic.

About this question

Subject: Chemistry · Chapter: Chemical Bonding and Molecular Structure · Topic: Ionic and Covalent Bonding

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