Tennessine astatine is estimated to be between 6.2 and 6.5 g/cm. The known isotopes of tennessine, Ts and Ts, are too short-lived to allow for chemical experimentation at present. Nevertheless, many chemical properties of tennessine have been calculated. Unlike the previous group 17 elements, tennessine may not exhibit the chemical behavior common to the halogens. For example, fluorine, chlorine, bromine, and iodine routinely accept an electron to achieve the more stable electronic configuration of a noble gas, obtaining eight electrons (octet) in their valence shells instead of seven. This ability weakens as atomic weight increases going down the group; tennessine would
Nonmetal Nonmetal In chemistry, a nonmetal (or non-metal) is a chemical element that mostly lacks metallic attributes. Physically, nonmetals tend to have relatively low melting and boiling points, and densities, are mostly brittle if solid, and are usually poor conductors of heat and electricity; chemically, they tend to have relatively high ionization energy, electron affinity, and electronegativity values, and gain or share electrons when they react with other elements or compounds. Seventeen elements are generally classified as nonmetals; most are gases (hydrogen, helium, nitrogen, oxygen, fluorine, neon, chlorine, argon, krypton, xenon and radon); one is a liquid (bromine), and a few