Atomic number 56
Barium
Alkaline earth metal
In the real world
Quick facts
- Atomic mass
- 137.33
- Group
- 2
- Period
- 6
- State (STP)
- solid
- Electronegativity
- 0.89
- Common ox. states
- +2
Properties
Electron configuration
[Xe] 6s²
- Ionization energy
- 502.9 kJ/mol
- Electron affinity
- 13.9 kJ/mol
- Melting point
- 1000.00 K (726.9 °C)
- Boiling point
- 2118.00 K (1844.8 °C)
How dangerous is it?
2/5 · Caution
A reactive metal whose danger is all about the compound. Soluble barium salts are poisonous, yet barium sulfate is so insoluble people swallow it for X-rays.
- ToxicImmediate
Soluble barium salts interfere with the muscles and the heart. (the soluble salts, not insoluble barium sulfate)
Soluble compounds are handled with gloves and kept from food; insoluble barium sulfate is safe enough for medical use.
How it bonds
Barium loses both 6s electrons to give Ba²⁺ in salts (BaSO₄, the "barium meal" used in X-ray imaging - insoluble enough that the toxic Ba²⁺ never gets absorbed). Burns green in fireworks.
