Monatomic in chemistry refers to an element occuring as a single atom. Helium gas is one such element and it can be found on the periodic table of elements. A synonym of monatomic is monoatomic.
All other noble gases fall under this classification include: helium, neon, argon, krypton, xenon, radon.
Certain solid elements can also be classified as being monatomic after having been put through a chemical seperation process of precipatation where the end product is a powder. Monoatomic gold is such a substance and this white powder will not be found on the periodic table of elements...read more...