Americium (Am)
Americium (Am) is element 95, an actinide. Atomic mass 243, configuration [Rn] 5f⁷ 7s². Properties, isotopes, oxidation states, uses and history, with an interactive 3D atom model.
Key facts
| Atomic number | 95 |
|---|---|
| Symbol | Am |
| Standard atomic weight | 243 |
| Category | Actinide |
| Period | 7 |
| State at room temperature | Solid |
| Electron configuration | [Rn] 5f⁷ 7s² |
| Valence electrons | 2 (Variable) |
| Common oxidation states | +3 |
| Common ions | No common ions |
| First ionization energy | 578 kJ/mol |
| Atomic radius | 175 pm |
| Density | 12 g/cm³ |
| Melting point | 1176°C |
| Boiling point | 2011°C |
Common uses
- Smoke detectors (Am-241)
- Neutron sources
Where it matters
- Domestic Safety (Ionization smoke detectors)
Hazards
- Radioactive (accumulates in bones)
History
| Discovered | 1944 |
|---|---|
| Discovered by | Glenn T. Seaborg et al. |
| Name | The Americas |