Get your free Ultimate Chemistry Cheat Sheet here: https://www.chemin10.com/optin?ims=jemvs&utm_source=YT+Periodic+Table Atomic and Ionic Radius Trends in the Periodic Table The periodic trend in atomic radius. Atomic radius increases as you go down a group in the Periodic Table because, with each successive period, you are adding an energy level resulting in the outermost electrons being further away from the nucleus. Today's chemistry question of the day: Which of the following pairs is listed in order of INCREASING radius? A. F, F- B. I, Cl C. K, K+ D. Na, Mg Join us at http://chemin10.com to receive the Chemistry Question of the Day delivered to your inbox, as well as more videos and an online chemistry community of like-minded chemistry students!