Medium MCQ +4 / -1 PYQ · JEE Mains 2023

The hybridization and magnetic behaviour of cobalt ion in $\mathrm{[Co(NH_3)_6]^{3+}}$ complex, respectively is :

  1. A $\mathrm{sp^3d^2}$ and paramagnetic
  2. B $\mathrm{sp^3d^2}$ and diamagnetic
  3. C $\mathrm{d^2sp^3}$ and diamagnetic Correct answer
  4. D $\mathrm{d^2sp^3}$ and paramagnetic

Solution

$\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ is diamagnetic with $\mathrm{d}^{2} \mathrm{sp}^{3}$ hybridisation of $\mathrm{Co}^{+3}$. <br/><br/> This is because $\mathrm{NH}_{3}$ is a strong field ligand and forces electrons to pair up in a $\mathrm{d}^{6}$ configuration.

About this question

Subject: Chemistry · Chapter: Coordination Compounds · Topic: Ligands and Coordination Number

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