unbinilium

Our question at the beginning of this essay was "are there more elements to be discovered?" The next elements would be ununennium (atomic number 119) and unbinilium (atomic number 120). The problems in trying to produce these elements by accelerating an ion beam into a target are the short half-lives of possible target elements and the extended times required for a successful observation of a new element. So far, elements 119 and 120 have eluded discovery. But you can expect that scientists will continue to search for new elements.

2017, Darrell D. Ebbing, Steven D. Gammon, “Atoms, Molecules, and Ions”, in General Chemistry, 11th edition, Boston, Mass.: Cengage Learning, →ISBN, page 46