JEE Main 2017ChemistryChemical Bonding and Molecular StructureMediumMCQ

JEE Main 2017 — Chemical Bonding and Molecular Structure Question with Solution

JEE Main 2017 (08 Apr Online)

Question

Which of the following is paramagnetic?

Choose an option

Show full solutionCorrect option: D
Correct answer
DB2

Step-by-step explanation

Number of e-

CO=14, NO+=14

O22-=18,  B2=10.

According to MOT,

CO:− σ1s2<σ*1s2<σ2s2<σ*2s2<π2px2=π2py2<σ2pz2

no unpaired e- so diamagnetic

B 2 :− σ1 s 2 < σ * 1 s 2 <σ2 s 2 < σ * 2 s 2 <π2 p x 1 =π2 p y 1

2 unpaired e-,so paramagnetic

O2−2:− σ1s2<σ*1s2<σ2s2<σ*2s2<σ2pz2<π2px2=π2py2<π*2px2=π*2py2

no unpaired e-, so diamagnetic

NO+:− σ1s2<σ*1s2<σ2s2<σ*2s2<π2px2=π2py2<σ2pz2

no unpaired e-, so diamagnetic.
 

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About this question

This is a previous-year question from JEE Main 2017, covering the Chemical Bonding and Molecular Structure chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.