Discovery Information
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Who: Sir Humphrey Davy |
When: 1808 |
Where: England |
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Name Origin
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Latin: calx, calcis (lime). |
"Calcium" in different languages. |
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Sources
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Obtained from minerals like chalk, limestone and marble. Very abundant. Makes up 3.5% of crust (making it the fifth most abundant
element). Occurs only in compounds. Calcium is found mostly in soil systems as limestone, gypsum (CaSO4 - 2H2O) and fluorite (CaF2). Stalagmites and stalactites contain calcium carbonate (CaCO3).
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Annual production is around 112 million tons. |
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Abundance
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Universe: 70 ppm (by weight) |
Sun: 70 ppm (by weight) |
Carbonaceous meteorite: 11000 ppm |
Earth's Crust: 41000 ppm |
Seawater: 390 ppm |
Human: |
1.4 x 107 ppb by weight
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2.2 x 106 ppb by atoms
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Uses
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Used for dehydrating oils, decarburization and desulfurization of iron and its alloys, getter in vacuum tubes. Also used as an alloying agent for aluminium, copper and lead, a reducing agent for beryllium and used in fertilizer, concrete and plaster of paris.
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Calcium is an important component of a healthy diet. Calcium is an essential component shells, bones, teeth and plant structures. |
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History
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Calcium was prepared as lime by the Romans under the name calyx in the 1st century A.D., but the metal was not discovered
until 1808. Berzelius and Pontin prepared calcium amalgam by electrolizing lime in mercury. Davy was then successful in isolating the impure metal. Why did it take so long? Calcium is the fifth most abundant metallic element in the earth's crust, but is never found in the elemental form because it is so reactive. It is found in limestone (CaCO3) gypsum (CaSO4.2H2O) and fluorite (CaF2).
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Notes
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Calcium is an important component of a healthy diet. A deficit can affect bone and teeth formation, while over retention can
cause kidney stones. Vitamin D is needed to absorb calcium. Dairy products, such as milk and cheese, are a well-known source
of calcium.
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Hazards
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Pure calcium is a shiny soft metal that will react violently with water to release hydrogen and calcium hydroxide. Skin contact may cause burns.
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