If there is one half-remembered chemical fact that most of us carry from our schooldays, it is that the inert or “noble” gases do not react. ... The theory of chemical bonding explained why. The noble gases have full outer shells of electrons, and so cannot share other atoms' electrons to form bonds.

What do noble gases react with?

Noble Gases

They are generally chemically inert. This means that they do not react with other elements because they already have the desired eight total s and p electrons in their outermost (highest) energy level. The elements in this group are helium, neon, argon, krypton, xenon, and radon.

Why are some noble gases reactive?

Noble gases are the least reactive of all elements. That's because they have eight valence electrons, which fill their outer energy level. This is the most stable arrangement of electrons, so noble gases rarely react with other elements and form compounds.