What is ionization energy? Which family has the greatest and which family has the lowest? Why is the second ionization of Na so much higher than the first? Why is it so difficult to take away electrons from nonmetals as compared to metals?

Ionization Energy is the energy needed to take away an electron from a molecule or ion.


Family 7A has the greatest ionization energy, and the second group of earth elements has the lowest.

The second ionization of Na is higher than the first because it is much harder to get rid of the second electron because by that time the element only wants to become neutral, which is more easily obtained by gaining an electron as opposed to losing one.

It is more difficult to take away electrons from nonmetals as compared to metals because to follow the octet rule, nonmetals must gain an electron to fill their outer shells, where metals need to lose an electron to fufill the octet rule.