Uranium (U)
Uranium (U) is element 92, an actinide. Atomic mass 238.02891, configuration [Rn] 5f³ 6d¹ 7s². Properties, isotopes, oxidation states, uses and history, with an interactive 3D atom model.
Key facts
| Atomic number | 92 |
|---|---|
| Symbol | U |
| Standard atomic weight | 238.02891(3) |
| Category | Actinide |
| Period | 7 |
| State at room temperature | Solid |
| Electron configuration | [Rn] 5f³ 6d¹ 7s² |
| Valence electrons | 2 (Variable) |
| Common oxidation states | +6 |
| Common ions | No common ions |
| Electronegativity (Pauling) | 1.7 |
| First ionization energy | 598 kJ/mol |
| Atomic radius | 175 pm |
| Density | 19.1 g/cm³ |
| Melting point | 1134°C |
| Boiling point | 4131°C |
| Specific heat | 0.116 J/(g·°C) |
Common uses
- Nuclear fuel
- Armor plating (Depleted U)
- Yellow glass (historical)
Where it matters
- Nuclear Age (Fission power, Atomic weapons)
- Geothermal heat (Earth's core)
Hazards
- Radiotoxic and chemotoxic (kidney damage)
History
| Discovered | 1789 |
|---|---|
| Discovered by | Martin Heinrich Klaproth |
| Name | Planet Uranus |