Arsenic vs Americium
| Property | As Arsenic | Am Americium |
|---|---|---|
| Atomic number | 33 | 95 |
| Symbol | As | Am |
| Name | Arsenic | Americium |
| Category | metalloid | actinide |
| Standard Atomic Weight | 74.921595 u | 243 u |
| Period | 4 | 7 |
| Group | 15 | N/A |
| Block | p | s |
| Phase at STP | solid | solid |
| Electron configuration | [Ar]4s23d104p3 | [Rn]7s25f7 |
| Oxidation states | [-3, -2, -1, 0, 1, 2, 3, 4, 5] | [2, 3, 4, 5, 6, 7] |
| Electronegativity (Pauling) | 2.18 | 1.3 |
| Electron affinity | 0.81 eV | 0.1 eV |
| Density | 5776 kg/m³ | 1.369000e+4 kg/m³ |
| Melting point | 816.85 °C | 1175.85 °C |
| Boiling point | 613.85 °C | 2010.85 °C |
| Discovery year | 1250 | 1944 |