109 - Meitnerium transition metal
Discovered by Gesellschaft für Schwerionenforschung in 1982
Meitnerium is a chemical element with symbol Mt and atomic number 109. It is an extremely radioactive synthetic element (an element not found in nature that can be created in a laboratory). The most stable known isotope, meitnerium-278, has a half-life of 7.6 seconds.
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 | 15 | 2 in 6s + 6 in 6p + 7 in 6d |
| 7 | 2 | 2 in 7s |
Electron shells
278 u Atomic Mass
9 Group
37.4 g/cm³ Density
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d7 Electron Configuration
*[Rn] 5f14 6d7 7s2 Electron Configuration (semantic)
109 Electrons
7 Number of Shells
159 Neutrons
109 Atomic Number
7 Period
Solid Phase
109 Protons