Untriunium

Untriunium is the temporary systematic name assigned to the hypothetical chemical element with atomic number 131. No element with this name or atomic number has been confirmed.

Connect

Atomic number: The number of protons in an atom’s nucleus, which defines its chemical element. Untriunium’s proposed identity is fixed by its defining value: 131 protons.
Superheavy element: A chemical element with an atomic number near or above 104, whose nuclei are difficult to produce and study. Element 131 would lie far beyond the known superheavy elements.
IUPAC: The international scientific organization that standardizes chemical nomenclature, terminology, and measurement. IUPAC established the systematic temporary naming rules used for undiscovered elements.
Nuclear fission: A nuclear reaction in which a heavy nucleus splits into lighter nuclei, releasing energy and often neutrons. Any synthesized element 131 nucleus would likely face competing decay pathways, including fission.
Periodic table: A tabular arrangement of chemical elements ordered chiefly by atomic number and recurring chemical properties. Element 131 would extend the table beyond its currently confirmed elements.
Island of stability: A predicted region of enhanced nuclear stability among superheavy nuclides with particular proton and neutron numbers. It motivates speculation about whether very heavy nuclei could survive long enough to study.
Element 119: The unconfirmed chemical element with atomic number 119, which would begin the periodic table’s eighth period. Its search illustrates the experimental frontier that precedes still more distant elements such as 131.
Alpha decay: Radioactive decay in which a nucleus emits a helium-4 nucleus and becomes a lighter nuclide. Alpha-decay chains could provide evidence for an element 131 isotope if one were created.
IUPAC systematic element name: A temporary element name formed from numerical roots for each digit of an element’s atomic number, followed by “-ium.” “Untriunium” encodes the digits of atomic number 131 under this naming system.
Nuclear shell model: A model describing protons and neutrons as occupying quantized energy levels inside an atomic nucleus. Its predicted nuclear shells help estimate whether nuclei near element 131 might be stable.