Strontium (Sr)
Strontium (Sr) is element 38 of the periodic table, an alkaline earth metal in period 5 and group 2. Its standard atomic weight is 87.62, so one mole of strontium atoms has a mass of 87.62 g. At room temperature it is a solid; it melts at 776.85 °C and boils at 1381.85 °C.
| Atomic number | 38 |
|---|---|
| Symbol | Sr |
| Standard atomic weight | 87.62 |
| Molar mass | 87.62 g/mol |
| Category | Alkaline earth metal |
| Group | 2 |
| Period | 5 |
| Block | s-block |
| Electron configuration | [Kr] 5s2 |
| Oxidation states | +2 |
| Electronegativity (Pauling) | 0.95 |
| Atomic radius (van der Waals) | 249 pm |
| First ionisation energy | 5.695 eV (549.5 kJ/mol) |
| Electron affinity | — |
| State at room temperature | Solid |
| Melting point | 1050 K (776.85 °C) |
| Boiling point | 1655 K (1381.85 °C) |
| Density | 2.64 g/cm³ |
| Discovered | 1790 |
Group 2
Calculate with Strontium
Atomic weight: IUPAC CIAAW standard atomic weight. 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.