Name Origin: The name Barium comes from the Greek word “barys” which means “heavy”.

Symbol: Ba

Classification: Alkaline Earth Metals


Physical Properties-

Description: Barium is a silvery-white, soft, metallic element. In its elemental form it will oxidize easily very quickly.       

Crystal Structure: body-centered cubic (bcc)

Color: silvery-white

Taste: unknown


Body-Centered Cubic Crystal Structure

Intensive Properties-

Density @ 293 K: 3.51 g/cm3

Boiling Point: 2143K [1870 °C (3398 °F)] Melting Point: 1000K [727 °C (1341 °F)]


Chemical Properties-


  • Barium is found in nature in compounds never in the elemental form. 
  • Barium reacts with almost all of the nonmetals.
  • Barium forms oxides in air at room temperature and should be kept under petroleum or other suitable oxygen-free liquids to exclude air.
  • Barium reduces water and dilutes acids to hydrogen
  • Barium reacts vigorously with water to form a hydroxide.
  • Barium burns in air to form a peroxide, which produces hydrogen peroxide when treated with water.
  • Barium may spontaneously ignite in  moist air.





Barium in a Cup

Sources: Elemental barium is never found in nature since it reacts with oxygen in the air, forming barium oxide (BaO), and with water, forming barium hydroxide (Ba(OH)2). Barium is most commonly found as the mineral barium sulphate (BaSO4) and witherite (BaCO3). Though it is primarily produced through the electrolysis of barium chloride (BaCl2).




Barium Sulphate

Toxicity: Barium in elemental form is extremely toxic to people and animals. The health effects of the different barium compounds depend on the compounds solubility in water. Barium compounds that do not dissolve well in water are not harmful and are even used by doctors for medical purposes. Those barium compounds that do dissolve well in water may cause harmful health effects in people. Ingesting high levels of barium compounds that dissolve well in water has results in difficulties in breathing, increases blood pressure, changes in heart rhythm, Stomach irritation, brain swelling, muscle weakness, and damages to the liver, kidney, heart, and spleen.





Atomic Structure:

Atomic Number: 56

Atomic Mass: 137.327 amu

Electron Configuration: 1s22s22p63s23p63d104s24p64d105s25p66s2


Barium's Electron Configuration


In elemental form:

  • Barium is used as a “scavenger” for oxygen in vacuum tubes.


In Compound Form:

  • Barium Sulphate (BaSO4) is used in medical X-ray examinations. Its density and dullness to X-rays enables scanning of internal body tissues.
  • Barium Nitrate (Ba(NO3)2 ) is also used in fireworks to give a greenish color.
  • Barium Carbonate (BaCO3) is used to make glass stronger.
  • Barium Sulphate (BaSO4)  is used as a drilling "mud" in oil exploration, where its density prevents the escape of hydrocarbons from the drill hole.
  • Barium Sulphate is used as a shield to prevent the emission of high intensity radiation from television screens.
  • A Nickel Barium alloy is used in sparkplug wire and electron tube components because of the high amount of electrons given off.






A Barium Sulphate Enema


Karl Wilhelm Scheele, a Swedish scientist, was the first to discover the compound Barium Oxide in 1774. He observed a new element in Bononian phosphorus, which gave off a sulphate. This sulphate was insoluble in water and not otherwise recognizable. Though Sir Humphrey Davy, a British Chemist, was the first to isolate elemental barium. He did so in 1808 in London, England. He achieved the isolation by the electrolysis of molten baryta, Barium Oxide (BaO).  


Sir Humphrey Davy

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