#f-block

Which element belongs to the f-block of the periodic table?

f-block elements have electrons filling f-orbitals (lanthanoids and actinoids). Ce (Z=58) is an f-block element, while Sc (d-block), Rb (s-block), and Xe (p-block) are not.

Ref: NCERT Class 11 Chemistry > Chapter 3: Classification of Elements and Periodicity in Properties > Topic: Modern Periodic Law and Present Form - Long Form Periodic Table