| Attribute | Americium × | Manganese × |
|---|---|---|
| Standard state | Solid | Solid |
| Electron configuration | [Rn]7s²5f⁷ | [Ar]4s²3d⁵ |
| Atomic mass (u) | 243.06138 | 54.93804 |
| Electronegativity (pauling scale) | 1.3 | 1.55 |
| Oxidation states |
|
|
| Ionization energy (eV) | 5.993 | 7.434 |
| Atomic radius (van der waals) (pm) | 244 | 197 |
| Boiling point (K) | 2284 | 2334 |
| Melting point (K) | 1449 | 1519 |
| Density (g/cm³) | 13.69 | 7.3 |
| Atomic number | 95 | 25 |
| Group name | Actinide | Transition metal |
| Discovered (year) | 1944 | 1774 |
| Symbol | Am | Mn |