the elements in which electrons are progressively filled in 4f-orbital are called


Lanthanoid are known for their 4 f orbitals so the electrons are also filled in these orbitals.

For example, [Xe] 4f7 5d1 6s2= Electronic Configuration of Gadolinium


This is an element present iin the lanthanoid series and has electrons present in the 4f orbitals.


(Diagram of Lanthanoids).

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