61Pm
Element 61
Promethium
Lanthanides
Promethium, originally prometheum, is a chemical element with the symbol Pm and atomic number 61.
Key data
- Atomic number
- 61
- Atomic mass
- 145.000 u
- Group / Period
- 3 / 6
- Block
- f-block
- Phase at STP
- Solid
- Density
- 7.26 g/cm³
- Melting point
- 1041.8 °C
- Boiling point
- 2999.8 °C
- Electron configuration
- [Xe] 4f5 6s2
Common uses
- •Glow-in-the-dark dials
- •Beta-radiation sources
- •Nuclear batteries
Discovery
Year: 1945
Discovered by: Chien Shiung Wu
Named by: Isotopes of promethium
Frequently asked questions
What is the atomic number of Promethium?
Promethium has atomic number 61. Its symbol is Pm and its atomic mass is 145 u.
What category of element is Promethium?
Promethium is classified as lanthanides. It sits in group 3, period 6 of the periodic table.
What is Promethium used for?
Common uses of Promethium include: Glow-in-the-dark dials, Beta-radiation sources, Nuclear batteries.
When was Promethium discovered?
Promethium was discovered in 1945 by Chien Shiung Wu.
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