Barium
⚕️ In Your World
Barium is best known for its role in medicine. A thick, milkshake-like drink of barium sulfate is given to patients for a "barium meal" X-ray. Because barium is opaque to X-rays, this coats the digestive tract and allows doctors to see the stomach and intestines clearly. Barium compounds are also used to create a pale green color in fireworks and as a filler in plastics and rubber.
📖 The Discovery Story
Barium compounds were known to alchemists in the Middle Ages. The "Bologna Stone," a pebble of barite (barium sulfate) found near Bologna, Italy, was famous for glowing after being heated. The element itself was first isolated in 1808 by Sir Humphry Davy through the electrolysis of molten barium salts. He named it "barium" after the mineral barite, which comes from the Greek word barys, meaning "heavy," because of the high density of its compounds.
📊 Properties at a Glance
| Phase at STP | Solid |
| Melting Point | 727 °C / 1341 °F |
| Boiling Point | 1897 °C / 3447 °F |
| Electron Configuration | [Xe] 6s² |
| Abundance in Earth's Crust | 0.0425% |
⚠️ Safety & Handling
All water-soluble or acid-soluble barium compounds are highly toxic. However, the barium sulfate used in medicine is safe because it is extremely insoluble and passes through the digestive system without being absorbed. Pure barium metal is highly reactive and must be stored under oil to prevent it from reacting with air.