Whats the element that has a full outer shell of electrons and is non reactive?
The atoms with a single outer electron or a single missing electron are all highly reactive. Sodium is more reactive than Magnesium. Chlorine is more reactive that Oxygen. Generally speaking, the closer an atom is to having a full electron shell, the more reactive it is. Atoms with one outer electron are more reactive than those with two outer electrons. Atoms that are one electron short of a full shell are more reactive than those that are two short.