 Discovery Information
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| Who: Sir Humphrey Davy |
| When: 1808 |
| Where: England |
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| Name Origin
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| Greek: barys (heavy or dense). |
| "Barium" in different languages. |
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| Sources
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| Found in barytine (BaSO4) and witherite (BaCO3), never found in pure form due to its high reactivity.
|
| Important mining areas are the UK, Italy, Czech Republic, the USA and Germany. Annual production is around 6 million tons. |
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| Abundance
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| Universe: 0.01 ppm (by weight) |
| Sun: 0.01 ppm (by weight) |
| Carbonaceous meteorite: 2.8 ppm |
| Earth's Crust: 500 ppm |
| Seawater: |
| Atlantic surface: 4.7 x 10-3 ppm
|
| Atlantic deep: 9.3 x 10-3 ppm
|
| Pacific surface: 4.7 x 10-3 ppm
|
| Pacific deep: 2 x 10-2 ppm
|
| Human: |
| 300 ppb by weight |
| 14 ppb by atoms |
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| Uses
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| An alloys with nickel is used in sparkplug wire. Barium oxide (BaO) is used in a coating for the electrodes of fluorescent lamps.
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| Barium sulfate is a good x-ray absorber, used in x-ray diagnostic work for obtaining images of the digestive system (barium meals and barium enemas).
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| Barium carbonate (BaCO3) is used in glassmaking and also as a rat poison and can be used in making bricks.
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| Barium nitrate (Ba(NO3)2) and barium chlorate are used to give fireworks green colours.
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|
| History
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| Barium was first identified in 1774 by Karl Scheele and extracted in 1808 by Sir Humphry Davy in England. The oxide was at first called barote, by Guyton de Morveau, which was changed by Antoine Lavoisier to baryta, from which "barium" was derived to describe the metal.
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| Notes
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| Barium is a metallic element that is chemically similar to calcium, yet is soft and in its pure form is silvery white resembling lead.
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| Must be stored under a petroleum-based fluid (such as kerosene) to remain pure. |
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| Hazards
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| All water or acid soluble barium compounds are extremely poisonous. At low doses, barium acts as a muscle stimulant, while higher doses affect the nervous system, causing
cardiac irregularities, tremors, weakness, anxiety, dyspnea and paralysis.
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