Atomic number: 56
Category: alkali earth metal
Density at 25°C: solid: density: 3.51 g·cm−3
Barium is perhaps most known in the medicine as a contrast agent (in the form of barium sulphate and water) for x-rays to show activity in the digestive tract. But barium compounds are used in fireworks to produce a green colour.
Curiosity: the symbol Ba is used as part of the art work title for the TV Drama Breaking Bad.
Use, natural applications or common combinations:
- drilling fluid
- removes unwanted gases (gettering) from vacuum tubes
- some alloys
- Standard atomic weight: 137.327(7)
- Melting point: 727 °C
- Boiling point: 1897 °C
- Radioactivity: mostly naturally stable, possibly some isotopes are radioactive but very long half-lives.