October 31 - November 3, 2004
Element of the Day
Saturday, October 16
The name comes from the Greek word "Magnesia" which is a city in
Thessaly. In 1618 a farmer at Epsom in England attempted to give his cows water
from a well. This they refused to drink because of the water's bitter taste.
However the farmer noticed that the water seemed to heal scratches and rashes.
The fame of Epsom salts spread. Eventually they were recognized to be magnesium
sulphate, MgSO4.
Discovered by: Magnesium was recognized as an element by Joseph Black Black recognized magnesium as an element in 1755. It was isolated by Sir Humphry Davy in 1808, who electrolyzed a mixture of magnesia (magnesium oxide, MgO) and mercuric oxide (HgO).
Uses: Magnesium is used in flares, tracer bullets, fireworks, and pyrotechnics, including incendiary bombs. It was used in flash photography. It is lighter than aluminum, and is used in alloys used for aircraft, car engine casings, and missile construction. It is used a reducing agent for the production of uranium and other metals from their salts. The hydroxide (milk of magnesia), chloride, sulphate (Epsom salts), and the citrate are used in medicine. Magnesium oxide is refractory and used as bricks and liners in furnaces. Magnesium is used to make organomagnesium compounds (Grignard reagents), useful in organic synthesis. Magnesium is also used in computers, PDAs, cell phones, camera bodies, and projection equipment for radio-frequency shielding. It is also an essential component of many enzymes and chlorophyll. Magnesium is used as a bulk metal, in lightweight alloys, and as a "sacrificial" electrode.
70,000 World War II Messerschmitt and Stuka dive bombers contained magnesium fuselages, engine parts, and wheels. The U.S. Convair B-36 bombers contained 10,000kg of magnesium. Today's jet engine parts, rockets, missiles, and helicopter rotor housings contain magnesium. And 1939-2003 Volkswagen Beetles incorporated magnesium in its castings in the transmission housing and in the air-cooled engine (25kg of magnesium).