Q.53:- Discuss the main characteristics of four blocks of elements in the periodic table? Give their general electronic configuration.

Answer:-
s-block elements:

• They are highly reactive elements and thus occurs in combined state. On moving down the group their reactivity increases.
• They have good reducing characters.
• They generally form electropositive ion by losing 1 or 2 electrons, that’s why they are electro positive in nature.
• They are good conductors of heat and electricity.

p-block elements:

• Most of the p-block elements show variable oxidation states.
• They include both metals and non-metals.
• They are generally covalent in nature.
• As move from left to right the non-metallic character of the element increases.
• On moving down the group metallic character increases.

d-block elements:

• d-block elements show variable oxidation states.
• They are generally paramagnetic in nature.
• Their compounds are generally coloured. Those which form complex compounds.
• Most of the elements and their compounds acts as catalyst.

f-block elements:

• They are generally heavy metals having high melting and boiling points.
• Their compounds are generally coloured.
• Variable oxidation states are generally shown by these elements.
• Most of Activities are radioactive.

General electronic configuration:
s-block —ns^1-2
p-block —ns² np^{1- 6}
d-block —(n -1) d^{1 -10} ns^0-2
f-block —(n – 2)f^0-14 (n -1) d^{0- 1} ns²