JEE Main202313 Apr 2023Morning ShiftChemistryd and f Block ElementsActual
The pair of lanthanides in which both elements have high third-ionization energy is:
Options
- ADy , Gd
- BLu , Yb
- CEu , Yb
- DEu , Gd
Correct answer
C. Eu , Yb
Step-by-step solution
Europium has an atomic number of 63 and a stable electronic configuration of [ Xe ] 4 f 7 6 s 2 . Ytterbium, on the other hand, has an atomic number of 70 and a stable electronic configuration of [ Xe ] 4 f 14 6 s 2 . Both have high 3 rd ionisation energy due to half filled & fully filled configuration respectively.