JEE Main 2021 — Coordination Compounds Question with Solution
From: JEE Main 2021 (Online) 22th July Evening Shift
Question
The total number of unpaired electrons present in [Co(NH3)6]Cl2 and [Co(NH3)6]Cl3 is :
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Correct answer
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Step-by-step explanation
[Co(NH3)6]Cl2
Co2+ : [Ar]3d74s04p0
For this complex 0 < P.E., so pairing of electron does not take place.
sp3d2 hybridisation
Total 3 unpaired electrons are present.
[Co(NH3)6]Cl3
Co3+ : [Ar]3d6 4s0 4p0
d2sp3 hybridistion
NH3 acts as SFL because 0 > P.E.
So, here all electrons becomes paired.
Co2+ : [Ar]3d74s04p0
For this complex 0 < P.E., so pairing of electron does not take place.
sp3d2 hybridisation
Total 3 unpaired electrons are present.
[Co(NH3)6]Cl3
Co3+ : [Ar]3d6 4s0 4p0
d2sp3 hybridistion
NH3 acts as SFL because 0 > P.E.
So, here all electrons becomes paired.
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