Ac
Actinium
Element 89 · Actinide · Period 7, Group 3
Solid · Discovered 1899
Atomic Properties
| Atomic Number | 89 |
| Atomic Mass | 227.02775u |
| Electron Configuration | [Rn]7s2 6d1 |
| Electronegativity | 1.1Pauling |
| Atomic Radius | 260pm |
| Ionization Energy | 5.17eV |
| Oxidation States | +3 |
Physical Properties
| Standard State | Solid |
| Melting Point | 1324K |
| Boiling Point | 3471K |
| Density | 10.07g/cm³ |
| Group Block | Actinide |
| Year Discovered | 1899 |