Standard atomic weight real life substances—for example, in pharmaceuticals and scientific research. Atomic weights are specific to single sources and samples of an element, such as the atomic weight of carbon in a particular bone from a particular archeological site. Standard atomic weight generalizes such values to the "range of atomic weights" which a chemist might expect to derive from many random samples from Earth. This range is the cause of the "interval notation" in some standard atomic weight values. Out of the 118 known chemical elements, 84 are stable and have this Earth-environment based value. Typically, such a value is, for example
Isotopes of tennessine Isotopes of tennessine Tennessine (Ts) is the most-recently synthesized synthetic element, and much of the data is hypothetical. As for any synthetic element, a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first (and so far only) isotopes to be synthesized were Ts and Ts in 2009. The longer-lived isotope is Ts with a half-life of 51 ms. The below table contains various combinations of targets and projectiles that could be used to form compound nuclei with atomic number 117. Between July 2009 and February 2010, the team at the JINR (Flerov