Monday, December 1, 2008

Strontium

Strontium
Sr
Atomic number: 38
Atomic mass: 87.62 amu
Melting point: 769 degC
Boiling point: 1384 degC
Who discovered it?
Strontium was discovered in the lead mines of a Scottish village named Strontian in 1787. Adair Crawford recognized it as differing from other barium minerals in 1790. Strontium itself was discovered in 1798 by Thomas Charles Hope, and metallic strontium was first isolated by Sir Humphry Davy in 1808 using electrolysis and announced by him in a lecture to the Royal Society on 30th June 1808.
What are its general properties?
Strontium is a grey/silvery metal that is softer than calcium and even more reactive in water, with which strontium reacts on contact to produce strontium hydroxide and hydrogen gas. It burns in air to produce both strontium oxide and strontium nitride, but since it does not react with nitrogen below 380°C it will only form the oxide spontaneously at room temperature.
What are sources for Strontium?
Strontium is found chiefly as celestite and strontianite (both minerals) The metal can be prepared by electrolysis (a method that chemists used to seperate chemically bonded elements and compounds by passing and electrical current through them) of the fused chloride mixed with potassium chloride, or is made by reducing strontium oxide with aluminum in a vacuum at a temperature at which strontium distills off.
What are its uses?
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. (that's right, the very magnets on your fridge! CHEMISTRY INVASION!)
What is its history?
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).
Other interesting things
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.

1 comment:

Unknown said...

I would like a extend a few words on the chemical properties of Strontium Hydroxide Exporters and its advantages.