Question

how does ionization energy relate to atomic radii

Answer 1

Ionization energy is the energy required for an atom to "pull" an electron from it.If the atomic radius is small, the electron is "more attracted" to the positive charge in the nucleus, which will require more energy.Hence,the smaller the atomic radius, the stronger the ionization energy. Also, atomic radii increases as it goes down the periodic table and as it goes left while ionization energy increases as you go up the periodic table and as you go right.