This is a question that I get asked so many times by my students, and to be honest I have never really been able to give a definitive answer – until now! On December 30th the International Union of Pure and Applied Chemistry (IUPAC) announced the official recognition of elements Uup, Uus and Uuo with atomic numbers of 115, 117 and 118 respectively. As yet the elements have not been named, but what this means is that the seventh row of the periodic table is now officially full.
These elements are synthesized by slamming lighter nuclei into each other and tracking the decay of the superheavy elements that were subsequently produced. These new elements may only exist for a fraction of a second, but that’s sufficient to get official recognition!