Promethium (Pm)
Promethium is the only radioactive lanthanide with no stable isotopes. It is used in nuclear batteries.
Properties of Promethium
- Atomic number
- 61
- Category
- Lanthanide
- Atomic mass
- 145 u
- Electron configuration
- [Xe] 4f⁵ 6s²
- Melting point
- 1315 K (1041.85 °C)
- Boiling point
- 3273 K (2999.85 °C)
- Density
- 7.26 g/cm³
- Electronegativity (Pauling)
- 1.13
- Appearance
- Metallic
- Discovered by
- Chien Shiung Wu (1945)
Facts about Promethium
- Promethium is named after Prometheus, the Greek god who stole fire from the gods!
- Promethium is radioactive — it barely exists in nature!
- Promethium was used in glow-in-the-dark watch dials!
- Promethium can be used to make nuclear-powered batteries for spacecraft!