The p-Block Elements-Notes
d-Block: Position and Electronic Configuration
“d-block elements” is the collective name for the groups 3 to 12, in which the d-orbitals are progressively filled in each of the four long periods.
As the d-block elements lie between the s and p block elements, they are also referred to as the transition elements.
Transition elements are those that have incompletely filled d-orbitals either in their elemental state or in any their chemically significant oxidation states.
The elements, zinc, cadmium and mercury, which have d-10 configuration, both in their elemental and stable oxidation states, are not considered transition elements.The general electronic configuration of the transition elements is (n – 1)d1-10 ns1-2