Atomic Properties
- Atomic Number
- 91
- Atomic Mass
- 231.0400 u
- Electron Configuration
- [Rn] 5f2 6d1 7s2
- Electronegativity
- 1.50
- Block
- f-block
- Group
- —
- Period
- 7
Physical Properties
- Phase (STP)
- solid
- Melting Point
- 1841.00 K
- Boiling Point
- 4300.00 K
- Density
- 15.3700 g/cm³
About Protactinium
Rare and highly radioactive; one of the rarest natural elements.
Isotopes of Protactinium
Protactinium has 1 naturally occurring isotope.
| Isotope | Mass Number | Atomic Mass (u) | Abundance | Type |
|---|---|---|---|---|
| 231Pa | 231 | 231.0358842 | 100.00% | Stable |
Data source: NIH PubChem (aggregated from IUPAC, NIST)