MCQ
Elements in which $4f$ orbitals are progressively filled are called as
  • A
    Transition elements
  • Lanthanides
  • C
    Actinides
  • D
    Inert gases

Answer

Correct option: B.
Lanthanides
b
In lanthanoids, electrons are progressively filled in $4$ orbital. The general electronic configuration for lanthanoids is $[ Xe ] \,4 f ^{1-14} \,5 d ^{0-1}\, 6 s ^2$

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