Question

What is ionization?

Answer 1

Welcome to OpenStudy. Ionization is when you remove the electrons in the outermost shell of an atom. When you go down the group, the period=number of shells increases. This means that the size of the atoms increases, which means the outermost shell gets further away from the nucleus. And so, the attraction between the nucleus and the electrons you want to remove on the outermost shell will decrease.