The elements of a periodic table can be divided into different blocks. They are classified on the basis of the shell occupied by their valence electrons.
The four types of blocks in the modern periodic table are:
· s block
· p block
· d block
· f block
Coming to your question, let’s discuss about s and p block elements.
· the elements of group 1 and 2 belong to s block
· these have one and two valence electrons in their outermost shell – the s-orbital
· the elements are basically metals
· group 1 elements – Li, Na, K, Rb, Cs
· group 2 elements – Be, Mg, Ca, Sr, Ba
· the elements of group 13, 14, 15, 16, 17, 18 belong to this block
· these have 3 – 6 electrons in their outermost shell
· the outermost shell belongs to p – orbital
· the elements are generally non – metals but it also consist of metalloids and some metals
Differences between s- and p- block elements:
S – block elements:
· the general electronic configuration of s – block elements is ns<sup>1-2</sup>
· these are metals
· these generally form ionic compounds. (except- Li and Be)
· they have a low EN as compared to p – block elements.
· These show oxidation states of +1 and +2.
Example- Li, Na, K etc.
P – block elements
· the general electronic configuration of p – block elements is ns<sup>2</sup>np<sup>1-6</sup>
· these include non – metals, metalloids and some metals too
· these can form both ionic and covalent compounds
· they have high EN as compared to s – block elements
· these show a varied variety of oxidation states.
Example – B, Al, In, C, N, O etc.
I hope this answer helps.