Polonium (Po)
Polonium (Po) is element 84 of the periodic table, a metalloid in period 6 and group 16. It has no stable isotope and no standard atomic weight; 209 is the mass number of its longest-lived isotope. At room temperature it is a solid; it melts at 253.85 °C and boils at 961.85 °C.
| Atomic number | 84 |
|---|---|
| Symbol | Po |
| Standard atomic weight | [209] (mass number of the longest-lived isotope) |
| Molar mass | [209] g/mol |
| Category | Metalloid |
| Group | 16 |
| Period | 6 |
| Block | p-block |
| Electron configuration | [Xe] 6s2 4f14 5d10 6p4 |
| Oxidation states | +4, +2 |
| Electronegativity (Pauling) | 2 |
| Atomic radius (van der Waals) | 197 pm |
| First ionisation energy | 8.417 eV (812.1 kJ/mol) |
| Electron affinity | 1.9 eV |
| State at room temperature | Solid |
| Melting point | 527 K (253.85 °C) |
| Boiling point | 1235 K (961.85 °C) |
| Density | 9.32 g/cm³ |
| Discovered | 1898 |
Group 16
Calculate with Polonium
Atomic weight: IUPAC CIAAW — no standard atomic weight; mass number in brackets. Other properties: PubChem (U.S. National Library of Medicine, public domain). Values such as melting point and radius depend on how they were measured; check a data book for precise work.