Quick Facts
| Property | Value |
|---|---|
| Symbol | Re |
| Atomic Number | 75 |
| Atomic Mass | 186.21 u |
| Category | Transition Metal |
| Period | 6 |
| Group | 7 |
| Block | d |
| Electron Configuration | [Xe] 4f¹⁴ 5d⁵ 6s² |
Physical Properties
| Property | Value |
|---|---|
| State at 20°C | Solid |
| Density | 21.02 g/cm³ |
| Melting Point | 3186°C (3459 K) |
| Boiling Point | 5596°C (5869 K) |
| Appearance | Silvery-gray metal |
History and Discovery
Discovered by: Walter Noddack, Ida Tacke, and Otto Berg Year of Discovery: 1925 Location: Berlin, Germany
Etymology
Named after the Rhine River (Latin "Rhenus").
Applications and Uses
- Jet engine superalloys (main use)
- Petroleum refining catalysts
- High-temperature thermocouples
- Electrical contacts
- Mass spectrometer filaments
Interesting Facts
- Last stable element to be discovered (1925)
- Third-highest melting point of all elements
- One of the rarest elements in Earth's crust
- Critical for jet engines in commercial aviation
- Most expensive common industrial metal