JIPMER2005Chemistryd and f Block Elements
The incorrect configuration is
Options
- AK =[ Ar ] 4 s^1
- BCr =[ Ar ] 3 d^5 4 s^1
- CCr =[ Ar ] 3 d^4 4 s^1
- DCu =[ Ar ] 3 d¹⁰ 4 s^1
Correct answer
C. Cr =[ Ar ] 3 d^4 4 s^1
Step-by-step solution
The correct configurations of K , Cu and Cr are [ Ar ] 4 s^1,[ Ar ] 3 d¹⁰ 4 s^1,[ Ar ] 3 d^5 4 s^1 respectively. As half filled and completely filled d orbitals are more stable, hence in case of Cr and Cu one electron shifts from 4 s orbital to 3 d orbital to give them stable electronic configuration.