NEETChemistryd and f Block Elements
Which of the following lanthanoid ions exhibits the highest spin-only magnetic moment?
Options
- AGd ³⁺
- BEu ³⁺
- CCe ³⁺
- DLu ³⁺
Correct answer
A. Gd ³⁺
Step-by-step solution
The spin-only magnetic moment depends on the number of unpaired electrons ( n ), given by = n(n+2) BM. The ion with the maximum number of unpaired electrons will have the highest magnetic moment. The electronic configurations of the given ions are: Gd ³⁺ (Z = 64): [ Xe ] 4 f ⁷ ( n = 7 ) Eu ³⁺ (Z = 63): [ Xe ] 4 f ⁶ ( n = 6 ) Ce ³⁺ (Z = 58): [ Xe ] 4 f ¹ ( n = 1 ) Lu ³⁺ (Z = 71): [ Xe ] 4 f ¹⁴ ( n = 0 ) Since Gd ³⁺ has the maximum number of unpaired electrons ( n = 7 ), it exhibits the highest spin-only magnetic mom