This document summarizes the key characteristics of different blocks in the periodic table. It discusses the s-block elements which include groups IA and IIA and their valence electron configurations. It then discusses the p-block which includes groups 13 to 18 and their common oxidation states. Next, it covers the d-block transition metals, their variable oxidation states, colored compounds, and catalytic properties. Finally, it briefly mentions the f-block lanthanide and actinide elements and their common oxidation states. It concludes by noting the trends of atomic radius across periods and down groups in the periodic table.

1. PERIODICITY
By Akanksha rajput
(MSc chemistry)

4. The s-block of the periodic table consists of
the first two groups :-
Groups IA (Alkali Metals)
Group IIA (Alkaline Earth Metals)
Hydrogen and Helium.
The general electronic configuration is ns¹
for Alkali metals and ns² for Alkaline earth
metals where n = 2 to 7.
Alkali metals (except Li) and the Alkaline
Earth metals exhibit photoelectric effect.
They shows flame coloration.
 The Alkali metals show only +1 oxidation
state, while Alkaline Earth metals show +2
oxidation state only.

5.  P Block consist of Group 13 (group IIIA) to
Group 17 (group VIIA ) along with the Group18
(zero group elements).
The General electronic configuration is as given
below :-
Group 13 (Boron family) :- ns² np¹
Group 14 (Carbon family) :- ns² np²
Group 15 (Nitrogen family) :- ns² np³
Group 16 (Oxygen family) :- ns² np
Group 17 (Halogen family) :- ns² np
Group 18 (Noble gases) :- ns² np6 (except Helium)
The oxidation states shown by different groups is
as follows :-
Boron family (Group 13) :- +3,+1
Carbon family ( Group 14) :- +4,+2,-4
Nitrogen family (Group 15) :- +5,+3, -3
Oxygen family ( Group 16) :- +6, +4, +2, -2
Halogen family (Group 17) :- +7, +5, +3, +1, -1
Noble gases ( Group 18) :- +8,+6, +4, +2

6. The general electronic configuration of d-block elements is
ns ² (n - 1) d¹ to ns ² (n - 1) d¹º .
Zn, Cd, Hg are not considered as transition elements.
Most of the compounds of transition elements are colored in the solid
as well as solution phase.
Mostly paramagnetic in nature.
They have high catalytic properties.
 They form complex compounds.

7. OXIDATION STATES:- The Transition elements show
variable oxidation state in their compounds. Reason for this
variable oxidation state is that there is a very small energy
difference in between (n-1)d and ns orbital. As a result ,electrons
of (n-1)d orbitals as well as ns-orbitals take part in bond
formation.

8. The general electronic configuration of the f-block elements is
given as :-
(n-2) f1-14, (n-1) s2 , p6 , d0-1, ns2 .
Lanthanides
The group of 14 elements from Cerium(58) to Lutetium(71) are
placed along with lanthanum in IIIB group called as Lanthanides.
Actinides
The group of 14 elements from Thorium(90) to Lawrencium(103)
are placed along with Actinium in IIIB group and called as
Actinides.
They show a common stable oxidation state +3 . Also some
Lanthanides show +2 and +4 oxidation states.

15. TRENDS IN PERIODIC TABLE :- It increases along the period and
decreases down the group.

18. It increases along the period and decreases down the group.

22. THANKS