ATOMIC RADIUS

ATOMIC RADIUS

 The average distance between the nucleus of an atom and the outermost orbit is called atomic radius, while considering atom as spherical.

Atomic radii decreases along the period from left to right. It is because positive charge on the nucleus increases due to increase in atomic number but no. of shells remains same. 

In A Group     Atomic radii increases down the group

            It is due to two factors.

i.          Increase In Number Of Shells

           In a group, no. of shells increases downward. Hence atomic radii increases.

ii.         Shielding Effect

It is the decrease in force of attraction between outermost electrons and the nucleus due to inner shell electrons.