Easy MCQ +4 / -1 PYQ · JEE Mains 2020

The bond order and the magnetic characteristics of CN- are :

  1. A 3, paramagnetic
  2. B $2{1 \over 2}$, paramagnetic
  3. C 3, diamagnetic Correct answer
  4. D $2{1 \over 2}$, diamagnetic

Solution

&nbsp;&nbsp;&nbsp; CN<sup>-</sup> has 14 electrons. <br><br>Moleculer orbital configuration of CN<sup>-</sup> is <br><br>$${\sigma _{1{s^2}}}\,\sigma _{1{s^2}}^ * \,\,{\sigma _{2{s^2}}}\,\,\sigma _{2{s^2}}^ * \,\,{\pi _{2p_x^2}} =\,{\pi _{2p_y^2}}\,{\sigma _{2p_z^2}}$$ <br><br>Here is no unpaired electron so it is diamagnetic. <br>N<sub>b</sub> = 10 <br><br>N<sub>a</sub> = 4 <br><br>$\therefore\,\,\,\,$ BO = ${1 \over 2}\left[ {10 - 4} \right]$ = 3

About this question

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

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