Quick Facts
| Property | Value |
|---|---|
| Symbol | Pr |
| Atomic Number | 59 |
| Atomic Mass | 140.91 u |
| Category | Lanthanide |
| Period | 6 |
| Group | 3 |
| Block | f |
| Electron Configuration | [Xe] 4f³ 6s² |
Physical Properties
| Property | Value |
|---|---|
| State at 20°C | Solid |
| Density | 6.77 g/cm³ |
| Melting Point | 931°C (1204 K) |
| Boiling Point | 3520°C (3793 K) |
| Appearance | Silvery, soft metal with yellowish tint |
History and Discovery
Discovered by: Carl Auer von Welsbach Year of Discovery: 1885 Location: Vienna, Austria
Etymology
Named from the Greek "prasios" (green) and "didymos" (twin), meaning "green twin," referring to the green salts it forms.
Discovery Story
Carl Auer von Welsbach separated praseodymium from neodymium in 1885. Both had been hidden in "didymium," which Carl Gustaf Mosander had believed to be an element since 1841.
Applications and Uses
- Praseodymium-neodymium magnets
- Green colorant for glass and ceramics (didymium glass)
- Lighter flints (mischmetal)
- Aircraft engine alloys
- Yellow ceramic pigment
Interesting Facts
- For 44 years, chemists believed didymium was a single element
- Praseodymium salts are distinctly green
- Used in specialized goggles for glass blowing
- Important component of high-strength magnets