MHT CET202615 April 2026Evening ShiftChemistryd and f Block ElementsActual
Which of the following elements has completely filled 4 f orbital at the expected ground state configuration?
Options
- ALa
- BYb
- CEu
- DGd
Correct answer
B. Yb
Step-by-step solution
The electronic configurations of the given elements in their ground state are: La (Z=57) : [ Xe ] 5d¹ 6s² Yb (Z=70) : [ Xe ] 4f¹⁴ 6s² Eu (Z=63) : [ Xe ] 4f⁷ 6s² Gd (Z=64) : [ Xe ] 4f⁷ 5d¹ 6s² Thus, Ytterbium ( Yb ) has a completely filled 4f orbital. Answer: Yb