Compare Element Properties
| Property | Pa Protactinium | ? N/A |
|---|---|---|
| Atomic number | 91 | N/A |
| Symbol | Pa | N/A |
| Name | Protactinium | N/A |
| Category | actinide | N/A |
| Standard Atomic Weight | 231.03588 u | N/A |
| Period | 7 | N/A |
| Group | N/A | N/A |
| Block | s | N/A |
| Phase at STP | solid | N/A |
| Electron configuration | [Rn]7s25f26d1 | N/A |
| Oxidation states | [2, 3, 4, 5] | N/A |
| Electronegativity (Pauling) | 1.5 | N/A |
| Electron affinity | 0.123 eV | N/A |
| Density | 1.537000e+4 kg/m³ | N/A |
| Melting point | 1571.85 °C | N/A |
| Boiling point | -273.15 °C | N/A |
| Discovery year | 1913 | N/A |