Ionization energies

[Giselle_Arreguin_2K]

How can you tell if an element is a metal vs nonmetal based on its ionization energy?

[George Kefalas 1D]

Hey, I believe metals will have pretty low ionization energies (below 800) while nonmetals have ionization energies hovering above 800 and around the 1000 mark.

[Charis Chiu 2F]

Metals tend to form cations, which means they lose electrons. Because they are easy to lose electrons, it means that their first ionization energies are lower. Nonmetals, on the other hand, gain electrons, so their first ionization energies are going to be much higher.