sentence: Ununpentium is in the center of the theoretical island of stability.
sentences_after: No stable isotopes of ununpentium have yet been found. Models predict that the stable isotope of ununpentium should have 184 neutrons. The stable isotope with 184 neutrons is 299Uup.
concept_name: ununpentium
headings: Ununpentium
categories: Chemical elements Metals