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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 :

Multiple Choice Options

  • A t2g4eg2t_{2g}^4e_g^2 and t2g6eg0t_{2g}^6e_g^0
  • B t2g6eg0t_{2g}^6e_g^0 and t2g6eg0t_{2g}^6e_g^0
  • C t2g6eg0t_{2g}^6e_g^0 and t2g4eg2t_{2g}^4e_g^2
  • D t2g4eg2t_{2g}^4e_g^2 and t2g4eg2t_{2g}^4e_g^2

Step-by-Step Verified Solution

[Ru(en)3 ]Cl2 :

Here CN = 6 so octahedral splitting happens.

'en' is strong field ligand so Δ\Delta 0 > P(pairing energy). That is why pairing of electrons happens.

Δ\Delta 0 = Energy gap between eg and t2g orbital.
JEE Main 2020 (Online) 3rd September Evening Slot Chemistry - Coordination Compounds Question 196 English Explanation 1

[Fe(H2O)6]Cl2 :

Here CN = 6 so octahedral splitting happens.

H2O is weak field ligand so Δ\Delta 0 < P(pairing energy). That is why no pairing of electrons happens.

Δ\Delta 0 = Energy gap between eg and t2g orbital. JEE Main 2020 (Online) 3rd September Evening Slot Chemistry - Coordination Compounds Question 196 English Explanation 2

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