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

Correct order of spin only magnetic moment of the following complex ions is :

(Given At.no. Fe : 26, Co : 27)

  1. A $\mathrm{[CoF_6]^{3-} > [FeF_6]^{3-} > [Co(C_2O_4)_3]^{3-}}$
  2. B $\mathrm{[FeF_6]^{3-} > [Co(C_2O_4)_3]^{3-} > [CoF_6]^{3-}}$
  3. C $\mathrm{[FeF_6]^{3-} > [CoF_6]^{3-} > [Co(C_2O_4)_3]^{3-}}$ Correct answer
  4. D $\mathrm{[Co(C_2O_4)_3]^{3-} > [CoF_6]^{3-} > [FeF_6]^{3-}}$

Solution

<p>${\left[ {Fe{F_6}} \right]^{3 - }}\buildrel {} \over \longrightarrow 5$ unpaired electrons</p> <p>$${\left[ {Co{{\left( {{C_2}{O_4}} \right)}_3}} \right]^{3 - }}\buildrel {} \over \longrightarrow 0$$ unpaired electron</p> <p>${\left[ {Co{F_6}} \right]^{3 - }}\buildrel {} \over \longrightarrow 4$ unpaired electrons</p> <p>So, correct answer is : (3)</p>

About this question

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

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