Barium is a soft, silvery-white metal, with a slight golden shade when ultrapure.[5]: 2 The silvery-white color of barium metal rapidly vanishes upon oxidation in air yielding a dark gray layer containing the oxide.
Physical state at 20 °C :
|
Solid. |
Odour threshold : | No data available. |
pH value : | Not applicable. |
Melting point [°C] : | 210 °C |
Decomposition point [°C] : | N/A |
Critical temperature [°C] : | N/A |
Auto-ignition temperature [°C] : | N/A |
Flammability (solid, gas) : | N/A |
Flash point [°C] : | N/A |
Boiling point [°C] : | N/A |
Initial boiling point [°C] : | N/A |
Final boiling point [°C] : | N/A |
Evaporation rate : | N/A |
Vapour pressure [20°C] : | N/A |
Vapour pressure mm/Hg : | N/A |
Vapour density : | N/A |
Density [g/cm3] : | 4.498 |
Relative density, gas (air=1) : | N/A |
Relative density, liquid (water=1) : | N/A |
Solubility in water [% weight] : | Slightly soluble |
Solubility in water : | N/A |
Log Pow octanol / water at 20°C : | No data available. |
Solubility : | N/A |
Viscosity at 40°C [mm2/s] : | N/A |
Explosive properties : | N/A |
Explosion limits - upper [%] : | N/A |
Explosion limits - lower [%] : | N/A |
Oxidising properties : | No data available. |
Barium, as a metal or when alloyed with aluminium, is used to remove unwanted gases (gettering) from vacuum tubes, such as TV picture tubes.
The barium mineral, benitoite (barium titanium silicate), occurs as a very rare blue fluorescent gemstone, and is the official state gem of California.