Tennessine has the largest atomic number among elements named after places in the United States.
Tennessine has atomic number 117 and the symbol Ts. It is a synthetic superheavy element in group 17, the halogen group. The name honors Tennessee, where Oak Ridge National Laboratory is located and where important contributions to the element’s discovery and production were made.
The element was first created through experiments involving researchers from the Joint Institute for Nuclear Research, Oak Ridge National Laboratory, Vanderbilt University, and Lawrence Livermore National Laboratory. The International Union of Pure and Applied Chemistry approved the name tennessine in 2016.
Other U.S.-related element names include berkelium, californium, and americium. Their atomic numbers are 97, 98, and 95 respectively, all lower than 117. Tennessine is highly radioactive, and only tiny numbers of atoms have been made.