105 - Dubnium transition metal
Discovered by Joint Institute for Nuclear Research in 1970
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.
Periodic table
| Shell | Electrons | Orbitals |
|---|---|---|
| 1 | 2 | 2 in 1s |
| 2 | 8 | 2 in 2s + 6 in 2p |
| 3 | 18 | 2 in 3s + 6 in 3p + 10 in 3d |
| 4 | 32 | 2 in 4s + 6 in 4p + 10 in 4d + 14 in 4f |
| 5 | 32 | 2 in 5s + 6 in 5p + 10 in 5d + 14 in 5f |
| 6 | 11 | 2 in 6s + 6 in 6p + 3 in 6d |
| 7 | 2 | 2 in 7s |
Electron shells
268 u Atomic Mass
5 Group
29.3 g/cm³ Density
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d3 Electron Configuration
*[Rn] 5f14 6d3 7s2 Electron Configuration (semantic)
105 Electrons
7 Number of Shells
157 Neutrons
105 Atomic Number
7 Period
Solid Phase
105 Protons