Ncert Exercises & Solutions

The elements in which electrons are progressively filled in 4f-orbitals are called:

1.	Actinoids	2.	Transition elements
3.	Lanthanoids	4.	Halogens

HINT : f - block elements are lanthanoids and actinoids.

Explanation:

The elements in which electrons are progressively filled in 4f-orbital are called lanthanoids.

Lanthanoids consist of elements from Z=58 (cerium) to 71 (lutetium).