Tennessine (Ts)

Tennessine has no naturally-occurring isotopes.


Tennessine is a superheavy artificial chemical element, previously known as eka-astatine or simply “element 117.” It is the second-heaviest of all the elements that have been created so far and is the second-to-last element of the 7th period of the periodic table. An article published in Physical Review Letters on April 5, 2010, claims the identification by a joint Russian-American collaboration of six atoms of the isotopes Ununseptium-293 (five atoms) and Ununseptium-294 (one atom) in fusion reactions between Calcium-48 and Berkelium-249. Decay chains involving eleven nuclei were identified by means of the Dubna Gas Filled Recoil Separator. The claims have not been confirmed. The name Tennessine recognizes the contribution of the Tennessee region, including Oak Ridge National Laboratory (ORNL), Vanderbilt University, and the University of Tennessee at Knoxville, to superheavy element research, including the production and chemical separation of unique actinide target materials for superheavy element synthesis at ORNL’s High Flux Isotope Reactor (HFIR) and Radiochemical Engineering Development Center (REDC).

Properties of Tennessine

Name Tennessine
Symbol Ts
Atomic number 117 
Atomic weight  [294] 
Standard state  Presumably a solid at 298 °K 
CAS Registry ID  87658-56-8
Group in periodic table  17 
Group name Halogen 
Period in periodic table  7
Block in periodic table  p-block 
Color  Unknown, but probably metallic and dark in appearance 
Classification  Unknown
Melting point No data available
Boiling point No data available
Density of solid  7.2 g/cm3 (predicted) 
Electron configuration [Rn]5f146d107s27p5 (predicted)

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