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QJEEM19Chd196: JEE Main 2019 Chemistry - Class 12 JEEM19Chd196 Solution: The complex ion that will lose its crystal field stabilization…
The complex ion that will lose its crystal field stabilization energy upon oxidation of its metal to +3 state is : 
Multiple Choice Options
- A [Fe(phen)3]2+
- B [Zn(phen)3]2+
- C [Co(phen)3]2+
- D [Ni(phen)3]2+
Step-by-Step Verified Solution
[Fe(phen)3]2+ [Fe(phen)3]3+
Here for Fe+2(3d6) :
CFSE = (-0.4 4 + 0.6 2) 0
= -0.4 0
for Fe+3(3d5) :
CFSE = (-0.4 3 + 0.6 2) 0
= 0
Here crystal field stabilization energy(CFSE) decreses.
Here for Fe+2(3d6) :
CFSE = (-0.4 4 + 0.6 2) 0
= -0.4 0
for Fe+3(3d5) :
CFSE = (-0.4 3 + 0.6 2) 0
= 0
Here crystal field stabilization energy(CFSE) decreses.