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Barium [Ba] locate me
CAS-ID: 7440-39-3
An: 56 N: 81
Am: 137.327 (7) g/mol
Group No: 2
Group Name: Alkaline earth metal
Block: s-block  Period: 6
State: solid
Colour: silvery white Classification: Metallic
Boiling Point: 2143K (1870°C)
Melting Point: 1000K (727°C)
Density: 3.51g/cm3
Discovery Information
Who: Sir Humphrey Davy
When: 1808
Where: England
Name Origin
Greek: barys (heavy or dense).
 "Barium" in different languages.
Sources
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.
Abundance
 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
Uses
An alloys with nickel is used in sparkplug wire. Barium oxide (BaO) is used in a coating for the electrodes of fluorescent lamps.
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).
Barium carbonate (BaCO3) is used in glassmaking and also as a rat poison and can be used in making bricks.
Barium nitrate (Ba(NO3)2) and barium chlorate are used to give fireworks green colours.
History
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.
Notes
Barium is a metallic element that is chemically similar to calcium, yet is soft and in its pure form is silvery white resembling lead.
Must be stored under a petroleum-based fluid (such as kerosene) to remain pure.
Hazards
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.