Silicon vs Protactinium
| Property | Si Silicon | Pa Protactinium |
|---|---|---|
| Atomic number | 14 | 91 |
| Symbol | Si | Pa |
| Name | Silicon | Protactinium |
| Category | metalloid | actinide |
| Standard Atomic Weight | 28.085 u | 231.03588 u |
| Period | 3 | 7 |
| Group | 14 | N/A |
| Block | p | s |
| Phase at STP | solid | solid |
| Electron configuration | [Ne]3s23p2 | [Rn]7s25f26d1 |
| Oxidation states | [-4, -3, -2, -1, 0, 1, 2, 3, 4] | [2, 3, 4, 5] |
| Electronegativity (Pauling) | 1.9 | 1.5 |
| Electron affinity | 1.385 eV | 0.123 eV |
| Density | 2329.6 kg/m³ | 1.537000e+4 kg/m³ |
| Melting point | 1413.85 °C | 1571.85 °C |
| Boiling point | 3264.85 °C | -273.15 °C |
| Discovery year | 1824 | 1913 |