Seaborgium is a synthetic chemical element with the symbol Sg and atomic number 106, whose most stable isotope 271Sg has a half-life of 1.9 minutes. A more recently discovered isotope 269Sg has a potentially slightly longer half-life (ca. 2.1 min) based on the observation of a single decay. Chemistry experiments with seaborgium have firmly placed it in group 6 as a heavier homologue to tungsten.Symbol: Sg
Atomic number: 106
Discovered: 1974
CAS ID: 54038-81-2
Van der Waals radius: 200 pm
Atomic mass: 266 u