Th
Thorium
Element 90 · 232.038 u
Thorium is a radioactive actinide being researched as a potential nuclear fuel.
Physical Properties
| Atomic Mass | 232.038 u |
| Density | 11.72 g/cm³ |
| Melting Point | 2115.0 K |
| Boiling Point | 5061.0 K |
| Appearance | Silvery, often with black tarnish |
| State at Room Temp | Solid |
Chemical Properties
| Electronegativity | 1.3 (Pauling) |
| 1st Ionization Energy | 587.0 kJ/mol |
| Electron Affinity | 112.72 kJ/mol |
| Oxidation States | +2, +3, +4 |
Atomic Properties
| Electron Configuration | [Rn] 6d2 7s2 |
| Atomic Radius | 180.0 pm |
| Van der Waals Radius | 237.0 pm |
Discovery
| Discovered By | Jons Jacob Berzelius |
| Discovery Year | 1829 |
| Location | Stockholm, Sweden |
| Named After | Thor, the Norse god of thunder |
About Thorium
Thorium is three times more abundant than uranium. Thorium reactors produce less long-lived waste and cannot melt down. Gas mantles for camping lanterns were historically made with thorium oxide.
Uses & Applications
Potential nuclear fuel, gas lantern mantles, high-temperature ceramics, welding electrodes, and aerospace alloys.
Fun Fact
Thorium reactors cannot melt down and produce waste dangerous for hundreds rather than thousands of years.
Isotopes
| Mass Number | Abundance | Half-Life | Stable |
| 228 | - | 1.9116 years | No |
| 230 | - | 75,380 years | No |
| 232 | 1.0% | 14.05 billion years | No |
Electron Configuration
[Rn] 6d2 7s2