JEE Main 2021 — Coordination Compounds Question with Solution
From: JEE Main 2021 (Online) 20th July Morning Shift
Question
The spin-only magnetic moment value for the complex [Co(CN)6]4 is __________ BM.
[At. no. of Co = 27]
[At. no. of Co = 27]
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Show full solutionCorrect answer: 2
Correct answer
2
Step-by-step explanation
[Co(CN)6]4
x + 6 (1) = 4
where, x, 6, 1 and 4 are the oxidation number of Co, number of CN ligands, charge on one CN and charge on complex.
x = +2, i.e. Co2+
Electronic configuration of Co2+ : [Ar]3d7 and CN is a strong field ligand which can pair electron of central atom.
It has one unpaired electron (n) in 4d-subshell.
So, spin only magnetic moment () = BM = BM = BM
where, n = number of unpaired electrons
= BM = 1.73 BM
Nearest integer = 2
x + 6 (1) = 4
where, x, 6, 1 and 4 are the oxidation number of Co, number of CN ligands, charge on one CN and charge on complex.
x = +2, i.e. Co2+
Electronic configuration of Co2+ : [Ar]3d7 and CN is a strong field ligand which can pair electron of central atom.
It has one unpaired electron (n) in 4d-subshell.
So, spin only magnetic moment () = BM = BM = BM
where, n = number of unpaired electrons
= BM = 1.73 BM
Nearest integer = 2
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