Question

Why charge to atomic radius of fluorine is highest?

Answer 1

due to small size and closeness of electrons the nuclei pulls the electron so greatly that it has high charge

Answer 2

Fluorine has a smaller radius than oxygen because the increasing charge in the nucleus draws electrons closer towards the center. F has 9 protons, while O only has 8, thus, F has a smaller radius. Fluorine has a smaller radius than chlorine because there are fewer shells.