element 11 science definition

An artificially produced radioactive element whose most stable isotope has a mass number of 285 and a half-life of about 34 seconds. Also called ununbium. See Periodic Table.

An artificially produced radioactive element whose most stable isotope has a mass number of 284 and a half-life of slightly less than half a second. Also called ununtrium. See Periodic Table.

An artificially produced radioactive element whose most stable isotope has a mass number of 289 and a half-life of approximately 2.7 seconds. Radioactive decay of all isotopes is chiefly by alpha-particle transmission. Also called ununquadium. See Periodic Table.

An artificially produced radioactive element whose most stable confirmed isotopes have mass numbers of 287 and 288 and half-lives of less than one second. Also called ununpentium. See Periodic Table.

An artificially produced radioactive element whose most stable isotope has a mass number of 293 and a half-life of less than one-tenth of a second. Also called ununhexium. See Periodic Table.

An artificially produced radioactive element, detected indirectly by decay, whose most stable isotope has a mass number of 294 and a half-life of less than two milliseconds. Also called ununoctium. See Periodic Table.