The d-and f-Block Elements — Chemistry STD 12 Science — Question

→ The d-block of the periodic table contains the elements of the groups 3-12 in which the d orbitals are progressively filled in each of the four long periods.
→ The name transition metals is often used to refer to the elements of d-block
→ There are mainly three series of the transition metals, 3d series (Sc to Zn), 4d series (Y to Cd) and 5d series (La and Hf to Hg).
→ The fourth 6d series which begins with Ac is still incomplete.