D and F-block Important Question answers Chemistry D and f-block important Question for Class 12

Those elements in which last electron enters the d-orbital of penultimate (n-1) shell

Those elements in which d-orbital is incompletely filled in their elementary form or in most common oxidation state.

Because they have d10 configuration in element form as well as in common oxidation state.

D-block elements are present between s and p-block elements

d-block elements are also known as Transition elements because they are present between s and p-block elements

There are 40 transition elements out of which 32 elements except (Sc,Y,La,Ac and Zn,Cd,Hg,Unb) are called typical transition elements

There are 40 transition elements out of which 8 elements (Sc,Y,La,Ac and Zn,Cd,Hg,Unb) are called non-typical transition elements

Cu, Ag, Au are coinage metals

Second last shell(n-1) is called penultimate shell

Third last shell(n-2) is called antepenultimate shell

Those elements in which last electron enters the f-orbital of antepenultimate(n-2) shell are called f-block elements

They are present within transition elements

Because they are present within transition elements

4f-series elements which follow lanthanum are called Lanthanides

5f-series elements which follow Actinium are called Actinides

5f –series elements after uranium are called trans-uranium elements