The Element Strontium
[Click for Isotope Data]
Atomic Number: 38
Atomic Weight: 87.62
Melting Point: 1050 K (777°C or 1431°F)
Boiling Point: 1655 K (1382°C or 2520°F)
Density: 2.64 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Metal
Period Number: 5 Group Number: 2 Group Name: Alkaline Earth Metal
What's in a name? Named for the town of Strontian, Scotland.
Say what? Strontium is pronounced as STRON-she-em.
History and Uses:
Strontium was discovered by Adair Crawford, an Irish chemist, in 1790 while studying the mineral witherite (BaCO3). When he mixed witherite with hydrochloric acid (HCl) he did not get the results he expected. He assumed that his sample of witherite was contaminated with an unknown mineral, a mineral he named strontianite (SrCO3). Strontium was first isolated by Sir Humphry Davy, an English chemist, in 1808 through the electrolysis of a mixture of strontium chloride (SrCl2) and mercuric oxide (HgO). Today, strontium is obtained from two of its most common ores, celestite (SrSO4) and strontianite (SrCO3), by treating them with hydrochloric acid, forming strontium chloride. The strontium chloride, usually mixed with potassium chloride (KCl), is then melted and electrolyzed, forming strontium and chlorine gas (Cl2).
Most of the strontium produced today is used in the manufacture of color television picture tubes. It is also used to refine zinc and is combined with iron to make magnets.
Two strontium compounds, strontium carbonate (SrCO3) and strontium nitrate (Sr(NO3)2), burn with a bright, red flame and are used in fireworks and signal flares. Strontium carbonate is also used to make certain kinds of glass and is the base material for making most other strontium compounds.
Strontium-90, a radioactive isotope of strontium, is a common product of nuclear explosions. It has a half-life of about 28.8 years and decays into yttrium-90 through beta decay. Strontium-90 is especially deadly since it has a relatively long half-life, is strongly radioactive and is absorbed by the body, where it accumulates in the skeletal system. The radiation affects the production of new blood cells, which eventually leads to death.
Estimated Crustal Abundance: 3.70×102 milligrams per kilogram
Estimated Oceanic Abundance: 7.9 milligrams per liter
Number of Stable Isotopes: 4 (View all isotope data)
Ionization Energy: 5.695 eV
Oxidation States: +2
3s2 3p6 3d10