Fluorine vs Promethium
| Property | F Fluorine | Pm Promethium |
|---|---|---|
| Atomic number | 9 | 61 |
| Symbol | F | Pm |
| Name | Fluorine | Promethium |
| Category | halogen | lanthanide |
| Standard Atomic Weight | 18.998403 u | 145 u |
| Period | 2 | 6 |
| Group | 17 | N/A |
| Block | p | s |
| Phase at STP | gas | solid |
| Electron configuration | [He]2s22p5 | [Xe]6s24f5 |
| Oxidation states | -1 | [2, 3] |
| Electronegativity (Pauling) | 3.98 | N/A |
| Electron affinity | 3.4011 eV | 0.129 eV |
| Density | 1.696 kg/m³ | 7260 kg/m³ |
| Melting point | -219.62 °C | 1041.85 °C |
| Boiling point | -188.12 °C | 2999.85 °C |
| Discovery year | 1886 | 1902 |