Last modified on 21 January 2019, at 13:11


Ununennium is a theoretical atom (following the IUPAC naming convention) which would have an atomic number of 119. This element does not exist in nature, and so far, it has not been created in a laboratory either despite multiple attempts. Since this atom would poses a single electron in its outer shell, it would be added to the periodic table under the alkali metals, and is expected to have similar properties. Since it has not yet been created, it has not been included in the current periodic table.[1][2]