Lithium (Li)
Lithium (Li) is element 3, an alkali metal. Atomic mass 6.94, configuration [He] 2s¹. Properties, isotopes, oxidation states, uses and history, with an interactive 3D atom model.
Key facts
| Atomic number | 3 |
|---|---|
| Symbol | Li |
| Standard atomic weight | [6.938,6.997] |
| Category | Alkali Metal |
| Group | 1 |
| Period | 2 |
| State at room temperature | Solid |
| Electron configuration | [He] 2s¹ |
| Valence electrons | 1 |
| Common oxidation states | +1 |
| Common ions | Li⁺ |
| Electronegativity (Pauling) | 0.98 |
| First ionization energy | 520 kJ/mol |
| Electron affinity | 59.63 kJ/mol |
| Atomic radius | 167 pm |
| Density | 0.534 g/cm³ |
| Melting point | 180.46°C |
| Boiling point | 1342°C |
| Specific heat | 3.582 J/(g·°C) |
Natural isotopes
- Li-6: Stable (7.6%)
- Li-7: Stable (92.4%)
Common uses
- Li-ion batteries
- Ceramics
- Lubricants
Where it matters
- Battery technology (EV revolution)
- Mental health (Mood stabilizers)
Hazards
- Reacts vigorously with water
- Corrosive
History
| Discovered | 1817 |
|---|---|
| Discovered by | Johan August Arfwedson |
| Name | Jöns Jakob Berzelius |