Sr
Strontium
STRONTIUM
ALKALINE EARTH METAL
| Atomic number: | 38 |
| Group numbers: | 2 |
| Period: | 5 |
| Electronic configuration: | [Kr] 5s2 |
| Formal oxidation number: | +2 |
| Electronegativities: | 0.95 |
| Atomic radius / pm: | 215.1 |
| Relative atomic mass: | 87.62(1) |
Strontium was discovered by Adair Crawford (GB) in 1789. Named after the village of Strontian in Scotland. It is a soft, malleable, silvery-yellow metal that is combustible in air and reacts with water. Exposed surfaces form protective oxide film. It ignites and burns readily. Strontium is found in minerals celestite and strontianite. Strontium is used in flares and fireworks for crimson colour. Strontium-90 is a long lived highly radioactive fallout product of atomic-bomb explosions. The price of 99 % pure strontium ingot is 322.30 € for 1000 g.
| Density / g dm-3: | 2540 | (293 K) |
| 2375 | (m.p.) | |
| Molar volume / cm3mol-1: | 34.50 | (293 K) |
| 36.89 | (m.p.) | |
| Electrical resistivity / µΩcm: | 23 | (20 °C) |
| Thermal conductivity / W m-1K-1: | 49 |
| Melting point / °C: | 777 |
| Boiling point / °C: | 1382 |
| Heat of fusion / kJ mol-1: | 9.16 |
| Heat of vaporization / kJ mol-1: | 154.4 |
| Heat of atomization / kJ mol-1: | 164.4 |
| First ionization energy / kJ mol-1: | 549.48 |
| Second ionization energy / kJ mol-1: | 1064.25 |
| Third ionization energy / kJ mol-1: | 4138.29 |
| in the atmosphere / ppm: | - |
| in the Earth's crust / ppm: | 260 |
| in the oceans / ppm: | 8 |
| Crystal structure: | face-centered cubic |
| Unit-cell dimensions / pm: | a=608.49 |
| Space group: | Fm3m |
| Isotope | Relative atomic mass | Mass percent (%) |
|---|---|---|
| 84Sr | 83.913425(4) | 0.56(1) |
| 86Sr | 85.909262(2) | 9.86(1) |
| 87Sr | 86.908879(2) | 7.00(1) |
| 88Sr | 87.905614(2) | 82.58(1) |
| Balanced half-reaction | Eo / V | |
|---|---|---|
| Sr2+ + 2e- → Sr(s) | - 2.89 |
| 37 Rubidium | ← | 38 Strontium | → | 39 Yttrium |
Citing this page:
Generalic, Eni. "Strontium." EniG. Periodic Table of the Elements. KTF-Split, 13 Feb. 2025. Web. {Date of access}. <https://www.periodni.com/sr.html>.
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