ESL Saigon logo



Name: Ununpentium (temporary)
Symbol: Uup
Number of Energy Levels: 7 (Predicted)
Electrons on the outer energy level: 5 (Predicted)
Atomic number: 115
Atomic Mass: 289 Amu (Atomic Mass Units) (Predicted)
Protons/Electrons: 115
Neutrons: 174
Density: 13.5 g/cm3 (Predicted)
Classification: Transition Metal (Predicted)

Ununpentium | Chemical elements

Ununpentium was discovered in 2003 at Joint Institute for Nuclear Research in Russia and Lawrence Livermore National Laboratory. Ununpentium was named according to IUPAC systematic element name and it is a temporary name. Its melting point is predicted to be at 670 K (400 °C, 750 °F) and its boiling point is predicted to be at 1400 K (1100 °C, 2000 °F).

Top 6 interesting facts about Ununpentium

  1. Ununpentium’s symbol (Uup) and its name are temporary.
  2. Ununpentium is a synthetic, superheavy, and extremely radioactive element.
  3. Ununpentium-289 is the most stable isotope of ununpentium (half-life of 220 milliseconds).
  4. Ununpentium is known as element 115 or eka-bismuth.
  5. Just 50 atoms of ununpentium were observed up to date.
  6. Ununpentium is predicted to have similar properties to its homologues nitrogen, phosphorus, arsenic, antimony, and bismuth but it should have several important differences as well.

Back to index