Beryllium vs Americium
| Property | Be Beryllium | Am Americium |
|---|---|---|
| Atomic number | 4 | 95 |
| Symbol | Be | Am |
| Name | Beryllium | Americium |
| Category | alkaline-earth-metal | actinide |
| Standard Atomic Weight | 9.012183 u | 243 u |
| Period | 2 | 7 |
| Group | 2 | N/A |
| Block | s | s |
| Phase at STP | solid | solid |
| Electron configuration | [He]2s2 | [Rn]7s25f7 |
| Oxidation states | [0, 1, 2] | [2, 3, 4, 5, 6, 7] |
| Electronegativity (Pauling) | 1.57 | 1.3 |
| Electron affinity | -0.52 eV | 0.1 eV |
| Density | 1850 kg/m³ | 1.369000e+4 kg/m³ |
| Melting point | 1286.85 °C | 1175.85 °C |
| Boiling point | 2470.85 °C | 2010.85 °C |
| Discovery year | 1797 | 1944 |