Hydrogen vs Protactinium
| Property | H Hydrogen | Pa Protactinium |
|---|---|---|
| Atomic number | 1 | 91 |
| Symbol | H | Pa |
| Name | Hydrogen | Protactinium |
| Category | nonmetal | actinide |
| Standard Atomic Weight | 1.007975 u | 231.03588 u |
| Period | 1 | 7 |
| Group | 1 | N/A |
| Block | s | s |
| Phase at STP | gas | solid |
| Electron configuration | 1s1 | [Rn]7s25f26d1 |
| Oxidation states | [-1, 1] | [2, 3, 4, 5] |
| Electronegativity (Pauling) | 2.2 | 1.5 |
| Electron affinity | 0.75419 eV | 0.123 eV |
| Density | 0.08988 kg/m³ | 1.537000e+4 kg/m³ |
| Melting point | -259.34 °C | 1571.85 °C |
| Boiling point | -252.87 °C | -273.15 °C |
| Discovery year | 1766 | 1913 |