Lawrencium
Lawrencium (铹, symbol Lr) is chemical element number 103, an Actinide in period 7 of the periodic table, with a standard atomic weight of about 266. Last actinide. Named after Ernest O. Lawrence, inventor of the cyclotron.
Properties
| Atomic number | 103 |
|---|---|
| Symbol | Lr |
| Atomic mass | 266 u |
| Category | Actinide |
| Period | 7 |
| Group | — |
| Electron configuration | [Rn] 5f¹⁴ 7s² 7p¹ |
| Electronegativity | 1.3 |
| Covalent radius | — |
| Density | 14.4 g/cm³ |
| Melting point | 1900 K |
| Boiling point | — |
| Discovery | Ghiorso et al., 1961 |
Overview
Last actinide. Named after Ernest O. Lawrence, inventor of the cyclotron. Lawrencium (Lr) holds position 103 in the periodic table, an Actinide in period 7. As an actinide it is typically radioactive and closely tied to nuclear technology.
With 3 electrons in its outermost shell, Lawrencium bonds accordingly; full configuration [Rn] 5f¹⁴ 7s² 7p¹, electronegativity 1.3. At room temperature it is normally a solid; it melts near 1900 K (1626.9 °C), has a density around 14.4 g/cm³.
Common applications range across Research. On the safety side, it carries a high hazard rating. It was first described by Ghiorso et al. in 1961. Use the comparison tool to line it up against other elements.
Electron shells
Electrons per shell: 2 · 8 · 18 · 32 · 32 · 8 · 3
Main uses
- Research
Hazard
Compounds containing Lawrencium
No compounds in this knowledge base contain Lawrencium yet.
Data sources
Atomic mass uses IUPAC (CIAAW) standard atomic weights; the covalent radius is from Cordero et al. (2008). Verify on the RSC Periodic Table, PubChem and Wikipedia. Educational reference only.