Medium MCQ +4 / -1 PYQ · JEE Mains 2021

Which one of the following species responds to an external magnetic field?

  1. A [Fe(H<sub>2</sub>O)<sub>6</sub>]<sup>3+</sup> Correct answer
  2. B [Ni(CN)<sub>4</sub>]<sup>2$-$</sup>
  3. C [Co(CN)<sub>6</sub>]<sup>3$-$</sup>
  4. D [Ni(CO)<sub>4</sub>]

Solution

1. ${[\mathop {Fe}\limits^{ + 3} {({H_2}O)_6}]^{3 + }}$<br><br>$F{e^{3 + }}:[Ar]3{d^5}$<br><br>Hybridisation : $s{p^3}{d^2}$<br><br>Magnetic nature : Paramagnetic (so this complex response to external magnetic field)<br><br>2. ${[Ni{(CN)_4}]^{2 - }}$<br><br>$N{i^{2 + }}:[Ar]3{d^8}$<br><br>Hybridisation : dsp<sup>2</sup><br><br>Magnetic nature : diamagnetic<br><br>3. ${[Co{(CN)_6}]^{3 - }}$<br><br>$C{o^{3 + }}:[Ar]3{d^6}$<br><br>Hybridisation : ${d^2}s{p^3}$<br><br>Magnetic nature : diamagnetic<br><br>4. $[Ni{(CO)_4}]$<br><br>$Ni:[Ar]3{d^8}4{s^2}$<br><br>Hybridisation : $s{p^3}$<br><br>Magnetic nature : diamagnetic

About this question

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

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