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QJEEM20Chbd5f: JEE Main 2020 Chemistry - Class 12 JEEM20Chbd5f Solution: The d-electron configuration of [Ru(en) 3 ]Cl 2 and [Fe(H 2 O)…
The d-electron configuration of [Ru(en)3 ]Cl2
and [Fe(H2O)6]Cl2 , respectively are :
and [Fe(H2O)6]Cl2 , respectively are :
Multiple Choice Options
- A and
- B and
- C and
- D and
Step-by-Step Verified Solution
[Ru(en)3 ]Cl2 :
Here CN = 6 so octahedral splitting happens.
'en' is strong field ligand so 0 > P(pairing energy). That is why pairing of electrons happens.
0 = Energy gap between eg and t2g orbital.

[Fe(H2O)6]Cl2 :
Here CN = 6 so octahedral splitting happens.
H2O is weak field ligand so 0 < P(pairing energy). That is why no pairing of electrons happens.
0 = Energy gap between eg and t2g orbital.
Here CN = 6 so octahedral splitting happens.
'en' is strong field ligand so 0 > P(pairing energy). That is why pairing of electrons happens.
0 = Energy gap between eg and t2g orbital.

[Fe(H2O)6]Cl2 :
Here CN = 6 so octahedral splitting happens.
H2O is weak field ligand so 0 < P(pairing energy). That is why no pairing of electrons happens.
0 = Energy gap between eg and t2g orbital.
