JEE Main 2021 — Coordination Compounds Question with Solution
From: JEE Main 2021 (Online) 1st September Evening Shift
Question
The Crystal Field Stabilization Energy (CFSE) and magnetic moment (spin-only) of an octahedral aqua complex of a metal ion (Mz+) are 0.8 0 and 3.87 BM, respectively. Identify (Mz+) :
Choose an option
Show full solutionCorrect option: D
Correct answer
DCo2+
Step-by-step explanation
Co2+ = [Ar] 3d74so
in [Co(H2O)6]2+, H2O will behave as weak field ligand
Co2+ = t2g5 , eg2
CFSE = (–0.4 × 5 + 2 × 0.6) Δ0 = –0.8 Δ0
Magnetic moment (spin only) can be calculated as :
where, = spin only magnetic moment and
n = number of unpaired electrons = 3
= = 3.87 BM
in [Co(H2O)6]2+, H2O will behave as weak field ligand
Co2+ = t2g5 , eg2
CFSE = (–0.4 × 5 + 2 × 0.6) Δ0 = –0.8 Δ0
Magnetic moment (spin only) can be calculated as :
where, = spin only magnetic moment and
n = number of unpaired electrons = 3
= = 3.87 BM
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