Atomic Properties
- Atomic Number
- 61
- Atomic Mass
- 145.0000 u
- Electron Configuration
- [Xe] 4f5 6s2
- Electronegativity
- 1.13
- Block
- f-block
- Group
- —
- Period
- 6
Physical Properties
- Phase (STP)
- solid
- Melting Point
- 1315.00 K
- Boiling Point
- 3273.00 K
- Density
- 7.2600 g/cm³
About Promethium
Only radioactive lanthanide; used in nuclear batteries and luminous paint.
Isotopes of Promethium
Promethium has 0 naturally occurring isotopes, plus 2 notable radioactive isotopes.
| Isotope | Mass Number | Atomic Mass (u) | Abundance | Type |
|---|---|---|---|---|
| 145Pm | 145 | 144.9127559 | — | Radioactive |
| 147Pm | 147 | 146.915145 | — | Radioactive |
Data source: NIH PubChem (aggregated from IUPAC, NIST)