Strontium

Strontium is a chemical element with the symbol **Sr** and the atomic number 38. An alkaline earth metal, strontium is a soft silver-white or yellowish metallic element that is highly reactive chemically. The metal turns yellow when exposed to air. It occurs naturally in the minerals celestine and strontianite. While natural strontium is stable, the synthetic 90Sr isotope is present in radioactive fallout and has a half-life of 28.90 years. Both strontium and strontianite are named after Strontian, a village in Scotland near which the mineral was first discovered. Strontium is most commonly found in real life as one of the main components of fireworks.


 * Uses**
 * fireworks (red flame), flares
 * 90Sr is a radioactive isotope produced by nuclear fallout. 90Sr has the potential for use as lightweight nuclear producing electricity
 * used to produce glass for colour television tubes
 * refining zinc
 * optical materials

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Characteristics

 * A grey, silvery metal
 * Softer than calcium and even more reactive than water
 * Occurs naturally in compounds with other elements such as in the minera,s strontianite and celestite
 * It is kept under a liquid hydrocarbon
 * Fine powder stontium metal will ignite spontaneously in air at room temperature
 * Natural strontium is a mixture of four stable isotopes

Discovery of Strontium
Author: Dr. Doug Stewart Strontium was recognized as distinct from barium in 1790 by Adair Crawford in a mineral sample from a lead mine near Strontian, Scotland. The mineral took its name from the Scottish town and was called strontianite (strontium carbonate). The metal was first isolated by Sir Humphry Davy in 1808 using electrolysis. Davy had built a very large 600-plate battery which he used to pass electricity through salts. He mixed magnesium oxide to a paste with (probably) strontium sulfate. He made a depression in the paste and placed mercury metal there to act as an electrode. Platinum was used as a counter electrode. When electricity was passed through the paste, a strontium-mercury amalgam formed at the mercury electrode. Davy removed the mercury from the amalgam by heating it to leave strontium metal. (1),(2). The element was named strontium by Davy after the mineral it was produced from. Davy discovered or isolated for the first time many alkali and alkali earth metals including potassium,sodium, barium, calcium and magnesium.

Examples of where srtontium can be found would be naturally in water and food.


 * Chemical Symbol: ||  || Sr ||
 * Atomic Number: ||  || 38 ||
 * Atomic Weight: ||  || 87.62 ||
 * Melting Point: ||  || 770 °C ||
 * Boiling Point: ||  || 1380 °C ||
 * Density of Solid: ||  || 2583 kg m-3 ||
 * Electron Configuration: ||  || 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 5s2 ||

Abundance

 * [|Amount in average human body (70kg):] ||  || 0.32 g ||
 * Average amount in Earth's crust: ||  || 370 ppm by mass ||
 * [|Average amount in seawater:] ||  || 7.9 mg L-1 ||