Dubnium
About Dubnium

Dubnium was produced in the 1960s by laboratories in both California and the former Soviet Union, leading to a protracted battle over naming rights that lasted until 1997. This 37-year debate has been referred to as the Transfermium Wars, as it concerned elements following fermium on the periodic table. Element 105 was finally named for the Joint Institute for Nuclear Research in Dubna, Russia in a compromise of sorts. Dubnium has no commercial applications.
Dubnium Properties
Dubnium is a D-Block, Group 5, Period 7 element. The number of electrons in each of Dubnium's shells is 2, 8, 18, 32, 32, 11, 2 and its electron configuration is [Rn] 5f14 6d3 7s2. In its elemental form, Dubnium's CAS number 53850-35-4. Dubnium’s appearance is unknown but it is thought to be silvery white or metallic gray. Little is known about the element and it has no known uses. Dubnium is a synthetic element and therefore is not naturally found in the environment. The discovery of Dubnium was made independently by Russian researchers at the Joint Institute for Nuclear Research in 1967 and then by American researchers at the University of California, Berkeley in 1970. Dubnium is named after Dubna, Russia, where it was first discovered.
Dubnium information, including technical data, properties, and other useful facts are specified below. Scientific facts such as the atomic structure, ionization energy, abundance on Earth, conductivity, and thermal properties are included.
General Properties
Symbol: | Db |
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Atomic Number: | 105 |
Atomic Weight: | 268 |
Element Category: | transition metal |
Group, Period, Block: | 5, 7, d |
Color: | unknown (presumably metallic/ silvery white/ gray) |
Other Names: | Dubnio |
Physical Properties
Melting Point: | N/A |
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Boiling Point: | N/A |
Density: | 29 (predicted) |
Liquid Density @ Melting Point: | N/A |
Density @ 20°C: | N/A |
Density of Solid: | 21600 (predicted) kg·m3 |
Specific Heat: | N/A |
Superconductivity Temperature: | N/A |
Triple Point: | N/A |
Critical Point: | N/A |
Heat of Fusion (kJ·mol-1): | N/A |
Heat of Vaporization (kJ·mol-1): | N/A |
Heat of Atomization (kJ·mol-1): | N/A |
Thermal Conductivity: | 0.58 W/cmK |
Thermal Expansion: | N/A |
Electrical Resistivity: | N/A |
Tensile Strength: | N/A |
Molar Heat Capacity: | N/A |
Young's Modulus: | N/A |
Shear Modulus: | N/A |
Bulk Modulus: | N/A |
Poisson Ratio: | N/A |
Mohs Hardness: | N/A |
Vickers Hardness: | N/A |
Brinell Hardness: | N/A |
Speed of Sound: | N/A |
Pauling Electronegativity: | N/A |
Sanderson Electronegativity: | N/A |
Allred Rochow Electronegativity: | N/A |
Mulliken-Jaffe Electronegativity: | N/A |
Allen Electronegativity: | N/A |
Pauling Electropositivity: | N/A |
Reflectivity (%): | N/A |
Refractive Index: | N/A |
Chemical Properties
Electrons: | 105 |
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Protons: | 105 |
Neutrons: | 157 |
Electron Configuration: | [Rn] 5f14 6d3 7s2 |
Atomic Radius: | 139 (estimated) |
Atomic Radius, non-bonded (Å): | Unknown |
Covalent Radius: | 149 (estimated) |
Covalent Radius (Å): | 1.49 |
Van der Waals Radius: | N/A |
Oxidation States: | 5, 4, 3 (predicted) |
Phase: | Solid (predicted) |
Crystal Structure: | N/A |
Magnetic Ordering: | N/A |
Electron Affinity (kJ·mol-1) | Unknown |
1st Ionization Energy: | 664.8 kJ·mol-1 (estimated) |
2nd Ionization Energy: | 1546.7 kJ·mol-1 |
3rd Ionization Energy: | 2378.4 kJ·mol-1 |
Identifiers
CAS Number: | 53850-35-4 |
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EC Number: | N/A |
MDL Number: | N/A |
Beilstein Number: | N/A |
SMILES Identifier: | [Db] |
InChI Identifier: | InChI=1S/Db |
InChI Key: | PUKKTGLVJQVIOF-UHFFFAOYSA-N |
PubChem CID: | 56951718 |
ChemSpider ID: | N/A |
Abundance
Earth - Total: | N/A |
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Mercury - Total: | N/A |
Venus - Total: | N/A |
Earth - Seawater (Oceans), ppb by weight: | N/A |
Earth - Seawater (Oceans), ppb by atoms: | N/A |
Earth - Crust (Crustal Rocks), ppb by weight: | N/A |
Earth - Crust (Crustal Rocks), ppb by atoms: | N/A |
Sun - Total, ppb by weight: | N/A |
Sun - Total, ppb by atoms: | N/A |
Stream, ppb by weight: | N/A |
Stream, ppb by atoms: | N/A |
Meterorite (Carbonaceous), ppb by weight: | N/A |
Meterorite (Carbonaceous), ppb by atoms: | N/A |
Typical Human Body, ppb by weight: | N/A |
Typical Human Body, ppb by atom: | N/A |
Universe, ppb by weight: | N/A |
Universe, ppb by atom: | N/A |
History
Discovered By: | Joint Institute for Nuclear Research |
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Discovery Date: | 1970 |
First Isolation: | N/A |
Dubnium Isotopes
Dubnium (Db) is an artificial element. Like all artificial elements, it has no stable isotopes.
Nuclide | Isotopic Mass | Half-Life | Mode of Decay | Nuclear Spin | Magnetic Moment | Binding Energy (MeV) | Natural Abundance (% by atom) |
---|---|---|---|---|---|---|---|
255Db | 255.10740(45)# | 1.7(5) s [1.6(+6-4) s] | a to 251Lr; SF | N/A | N/A | 1849.09 | - |
256Db | 256.10813(31)# | 1.9(4) s [1.6(+5-3) s] | a to 252Lr; SF ; EC to 256Rf | N/A | N/A | 1857.17 | - |
257Db | 257.10772(24)# | 1.53(17) s [1.50(+19-15) s] | a to 253Lr; SF ; EC to 257Rf | (9/2+) | N/A | 1865.25 | - |
258Db | 258.10923(37)# | 4.5(6) s | a to 254Lr; SF ; EC to 258Rf | N/A | N/A | 1873.33 | - |
259Db | 259.10961(23)# | 0.51(16) s | a to 255Lr | N/A | N/A | 1881.41 | - |
260Db | 260.11130(25)# | 1.52(13) s | a to 256Lr; SF ; EC to 260Rf | N/A | N/A | 1880.17 | - |
261Db | 261.11206(25)# | 1.8(4) s | a to 257Lr; SF | N/A | N/A | 1888.25 | - |
262Db | 262.11408(20)# | 35(5) s | a to 258Lr; SF ; EC to 262Rf | N/A | N/A | 1896.33 | - |
263Db | 263.11499(18)# | 29(9) s [27(+10-7) s] | a to 259Lr; SF | N/A | N/A | 1904.4 | - |
264Db | 264.11740(25)# | 3# min | Unknown | N/A | N/A | 1912.48 | - |
265Db | 265.1186(3)# | 15# min | Unknown | N/A | N/A | 1920.56 | - |
266Db | 266.12103(39)# | 20# min | Unknown | N/A | N/A | 1919.32 | - |
267Db | 267.12238(50)# | 73(+350-33) min | Unknown | N/A | N/A | 1927.4 | - |
268Db | 268.12545(57)# | 32(+11-7) h | Unknown | N/A | N/A | 1935.48 | - |
269Db | 269.12746(83)# | 3# h | Unknown | N/A | N/A | 1943.56 | - |
270Db | 270.13071(77)# | 1# h | Unknown | N/A | N/A | 1942.32 | - |