Lu
Lutetium is the last and heaviest lanthanide element.
Physical Properties
| Atomic Mass | 174.97 u |
| Density | 9.84 g/cm³ |
| Melting Point | 1925.0 K |
| Boiling Point | 3675.0 K |
| Appearance | Silvery-white metallic |
| State at Room Temp | Solid |
Chemical Properties
| Electronegativity | 1.27 (Pauling) |
| 1st Ionization Energy | 523.5 kJ/mol |
| Electron Affinity | 33.4 kJ/mol |
| Oxidation States | +3 |
Atomic Properties
| Electron Configuration | [Xe] 4f14 5d1 6s2 |
| Atomic Radius | 174.0 pm |
| Covalent Radius | 187.0 pm |
| Van der Waals Radius | 221.0 pm |
Discovery
| Discovered By | Georges Urbain, Carl Auer von Welsbach |
| Discovery Year | 1907 |
| Location | Paris, France / Vienna, Austria |
| Named After | Latin 'Lutetia' meaning Paris |
About Lutetium
Lutetium is the hardest and densest of the lanthanides. It is very expensive due to the difficulty of separation. Lutetium-176 is used for radiometric dating.
Uses & Applications
PET scan detectors, catalysts, LED phosphors, and radiometric dating.
Fun Fact
Lutetium is the most expensive naturally occurring rare earth element due to extreme difficulty of separation.
Isotopes
| Mass Number | Abundance | Half-Life | Stable |
| 175 | 0.9741% | - | Yes |
| 176 | 0.0259% | 37.6 billion years | No |
Electron Configuration
[Xe] 4f14 5d1 6s2