Discovery date : 1968-1970
Discovered by: Scientists at both Berkeley, California, USA, and Dubna, near Moscow, Russia
Origin of the name: Dubnium is named for the Russian town Dubna.
Allotropes :
~>DUBNIUM is a synthetic chemical element with symbol Db and atomic number 105. Dubnium is highly radioactive: the most stable known isotope, dubnium-268, has a half-life of just over a day. This greatly limits the extent of research on dubnium.
| FACT BOX | |||
| Group | 5 | Melting point | Unknown |
| Period | 7 | Boiling point | Unknown |
| Block | d | Density (g cm−3) | Unknown |
| Atomic number | 105 | Relative atomic mass | [268] |
| State at 20°C | Solid | Key isotopes | 268Db |
| Electron configuration | [Rn] 5f146d37s2 | CAS number | 53850-35-4 |
| ChemSpider ID | - | ChemSpider is a free chemical structure database | |
In 1968, a team led by Georgy Flerov at the Russian Joint Institute for Nuclear Research (JINR) bombarded americium with neon and made an isotope of element 105. In 1970, a team led by Albert Ghiorso at the American Lawrence Berkeley Laboratory (LBL) bombarded californium with neon and obtained isotope 261. They disputed the claim of the JINR people. The two groups gave it different names. The Russians called it neilsbohrium, while the Americans called it hahnium, both being derived from the names of prominent nuclear scientists.
Eventually, the International Union of Pure and Applied Chemistry (IUPAC) decided it should be called dubnium.