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| | Bohrium Basic information |
| | Bohrium Chemical Properties |
| | Bohrium Usage And Synthesis |
| Physical properties | Unnilseptium, or bohrium, is artificially produced one atom at a time in particle accelerators.In 1976 Russian scientists at the nuclear research laboratories at Dubna synthesizedelement 107, which was named unnilseptium by IUPAC. Only a few atoms of element 107were produced by what is called the “cold fusion” process wherein atoms of one element areslammed into atoms of a different element and their masses combine to form atoms of a newheavier element. Researchers did this by bombarding bismuth-204 with heavy ions of chromium-54 in a cyclotron. The reaction follows: Bi-209 + Cr-54 + neutrons = (fuse to form)Uns-262 + an alpha decay chain.
The melting point, boiling point, and density of element 107, as well as some other properties,are not known because of the small number of atoms produced. | | Isotopes | There are a total of 10 isotopes of unnilseptium (bohrium). Not all their half-livesare known. However, the ones that are known range from 8.0 milliseconds to 9.8 secondsfor Bh-272, which is the most stable isotope of bohrium and which decays into dubnium-268 through alpha decay. Only one isotope, Uns-261, has a decay mode that involvesboth alpha decay and spontaneous fission. All the others decay by alpha emission. | | Origin of Name | Named after the scientist Niels Bohr. | | History | Bohrium was discovered in 1976 by a team of scientists in Dubna, Russia, by bombarding bismuth-204 (204Bi) with a heavy nucleus of chromium-54 (54Cr). They published the results of this successful experiment and submitted a declaration of discovery. Later, in 1981, Peter Ambrüster, Gottfried Münzenberg, and their team in Darmstadt, Germany, confirmed the discovery, successfully preparing a single-atom isotope of bismuth-262. Subsequently, the International Union of Pure and Applied Chemistry (IUPAC) named this element bohrium.
| | Uses | None, except for research purposes. | | Definition | A synthetic
radioactive element first detected by
bombarding a bismuth target with
chromium nuclei. Only a small number of
atoms have ever been produced. | | Definition | bohrium: Symbol Bh. A radioactivetransactinide element; a.n. 107. Itwas first made in 1981 by Peter Armbrusterand a team in Darmstadt,Germany, by bombarding bismuth-209 nuclei with chromium-54 nuclei.Only a few atoms of bohrium haveever been detected. | | Hazard | Even though most isotopes of unnilseptium are alpha emitters, there is little radiationhazard because only a few atoms have been produced. |
| | Bohrium Preparation Products And Raw materials |
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