JEE Main 2020ChemistryCoordination CompoundsCrystal Field Theory CftmediumMCQ

JEE Main 2020Coordination Compounds Question with Solution

From: JEE Main 2020 (Online) 9th January Morning Slot

Question

[Pd(F)(Cl)(Br)(I)]2– has n number of geometrical isomers. Then, the spin-only magnetic moment and crystal field stabilisation energy [CFSE] of [Fe(CN)6]n–6, respectively, are:
[Note : Ignore the pairing energy]

Choose an option

Show full solutionCorrect option: A
Correct answer
A1.73 BM and –2.0 0

Step-by-step explanation

Complex [Pd(F)(Cl)(Br)(I)]2– (square planar geometry)-has 3 geometrical isomers.

n = 3

[Fe(CN)6]n–6 becomes [Fe(CN)6]3-

Here Oxidation state of Fe = +3

Fe+3 = [Ar]3d54s0

CN- is strong field ligand so it pairing of electrons happens.

E.C. according to CFT = ()

No. of unpaired e- = 1

Then Magnetic moment = = = 1.73 B.M

CFSE = [(–0.4 × 5) + (0.6 × 0)] 0 = –2.0 0

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About this question

This is a previous-year question from JEE Main 2020, 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.