Atomic radius decreases across the period and increases down the group.
The atomic radii is a periodic trend that decreases across the period and increases down the group. Periodic trends are properties of elements that increase or decrease down the group or across the period.
As more positive charges (protons) are added to the nucleus as we move across the period, the attractive force between electrons and protons increases. As such atomic radii decreases across the period.
Down the group, addition of more shells leads to increased electronic repulsion which causes that atomic radii of elements to increases as we move down the group.
Learn more: https://brainly.com/question/23784827
