JEE Main 2021ChemistryCoordination CompoundsMediumNumerical

JEE Main 2021Coordination Compounds Question with Solution

JEE Main 2021 (22 Jul Shift 1)

Question

The total number of unpaired electrons present in and is

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Show full solutionCorrect answer: 1
Correct answer
1

Step-by-step explanation

CoNH36Cl2
Co2+:[Ar] 3d74 s04p0
For strong field ligand and d7 configuration: t2g2,2,2 eg1,0 
Total 1 unpaired electron is present.
CoNH36Cl3
Co3+:[Ar]3 d64 s04p0
The hybridisation of the complex is d2sp3 hybridisation.
NH3 acts as strong field ligand, because Δ0>P.E..
So here all electrons becomes paired.

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About this question

This is a previous-year question from JEE Main 2021, covering the Coordination Compounds 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.