PTL:Strontium
From ChemEd Collaborative
The element is a metal in Group IIA - the alkaline earth metals - in the 5th period. Other elements in this group are beryllium (Be), magnesium (Mg), calcium (Ca), barium (Ba), and radium (Ra).
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Discovered
Strontium was isolated by Davy in 1808, and
Name
named for a town in Scotland.
Found
The element is found chiefly as the sulfate, SrSO4, in the mineral celestite.
Reactions
Freshly cut strontium has a silvery appearance, but rapidly turns yellow due to oxidation to the oxide, SrO. It burns in air with a characteristic red flame.
Strontium reacts rapidly with acids
Sr(s) + 2 HCl(aq) 
SrCl2(aq) + H2(g)
and water,
Sr(s) + 2 H2O Sr(OH)2(s) + H2(g)
but not with bases. Note that the reactivity of the alkaline earth metals with air, acids, and water increases with an increase in atomic number.
The metal is isolated by reducing SrO with Al metal in a vacuum and heating until the Sr metal distills off. The metal has a boiling point of 1384°C.
Uses
Volatile strontium salts give a beautiful crimson color to a flame, so they are used in [fireworks and other pyrotechnics].
The largest use of strontium is as the oxide in the manufacture of color television tubes. Strontium chloride has been used as a dental desensitizer, and the yellow chromate, SrCrO4, is an anticorrosive primer for zinc.
Natural strontium has four stable isotopes, but sixteen radioactive isotopes exist. Most important of these is strontium-90, a beta-emitter, which has a half-life of 29 years. It is found in the fallout from nuclear weapons and thus poses a health risk. The isotope is used in nuclear-electric power sources, valuable devices in space vehicles, remote weather stations, and navigational buoys.
Emission Spectra
This is the emission spectra for Strontium.
