Plutonium (Pu)
Plutonium (Pu) is element 94 of the periodic table, an actinide in period 7, in the f-block. It has no stable isotope and no standard atomic weight; 244 is the mass number of its longest-lived isotope. At room temperature it is a solid; it melts at 639.85 °C and boils at 3227.85 °C.
| Atomic number | 94 |
|---|---|
| Symbol | Pu |
| Standard atomic weight | [244] (mass number of the longest-lived isotope) |
| Molar mass | [244] g/mol |
| Category | Actinide |
| Group | f-block (actinide series) |
| Period | 7 |
| Block | f-block |
| Electron configuration | [Rn] 7s2 5f6 |
| Oxidation states | +6, +5, +4, +3 |
| Electronegativity (Pauling) | 1.28 |
| Atomic radius (van der Waals) | 243 pm |
| First ionisation energy | 6.06 eV (584.7 kJ/mol) |
| Electron affinity | — |
| State at room temperature | Solid |
| Melting point | 913 K (639.85 °C) |
| Boiling point | 3501 K (3227.85 °C) |
| Density | 19.84 g/cm³ |
| Discovered | 1940 |
Actinides
Calculate with Plutonium
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.