A noble gas is a chemical element appearing on the right end of the periodic table. The noble gasses are named for their tendency to not react with other atoms, thus making them 'noble'. This property is a result of having their outer electron orbital full. These elements are generally found as gasses because they rarely form compounds, which would make each molecule heavier and less likely to remain a gas. The noble gasses are helium, neon, argon, krypton, xenon, and radon. While noble gasses tend to not react with other atoms, they will in some circumstances. The larger the noble gas, the more likely it is to bond with other atoms. There were no known true noble gas compounds until xenon hexafluoride was synthesized in 1962.