105Db268.000
Transition Metald-blockRadioactive
Dubnium
Element 105 on the periodic table, symbol Db, group 5, period 7.
Dubnium is a chemical element with symbol Db and atomic number 105. It is named after the town of Dubna in Russia (north of Moscow), where it was first produced. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and radioactive; the most stable known isotope, dubnium-268, has a half-life of approximately 28 hours.
Properties
- Atomic Number
- 105
- Atomic Mass
- 268.0000 u
- Group
- 5
- Period
- 7
- Block
- d-block
- Category
- Transition Metal
- State at 25 °C
- Solid
- Melting Point
- Not measured
- Boiling Point
- Not measured
- Density
- 29.3 g/cm³
- Atomic Radius
- Not measured
- Electronegativity
- Not measured
- Oxidation States
- +5
- Abundance in Crust
- Vanishingly rare
- Discovered
- 1967
- Discovered By
- Joint Institute for Nuclear Research
Electron Configuration
*[Rn] 5f14 6d3 7s2
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d3
Elements near Dubnium
Elements in the same group share the number of outer electrons and behave in similar ways. Elements in the same period share a shell, so they change steadily from left to right.