Question

6. What is atomic size and what happen when we move left to right and top to bottom.​

Answer 1

In general, the atomic radius decreases as we move from left to right in a period and it increases when we go down a group. This is because in periods the valence electrons are in the same outermost shell.

Answer 2

The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons

Explanation:

atomic size increases as we move top to bottom and decreases as we move from left to right