Write scientific reasons.

Atomic radius goes on increasing down a group.

Atomic radius goes on increasing down a group because:

⇒ Down a group, the atomic number increases one by one as a result nuclear charge increases.

⇒ The outer electrons are adding in a new valence shell.

⇒ Therefore, the distance between the outermost electron (valence electron) and the nucleus is also increasing

⇒ Therefore, the size of the atom increases with increase I atomic number.

Number of shells are increasing down a group