Barium - ASCII Periodic Table of the Elements

ASCII PERIODIC TABLE OF THE ELEMENTS

  Ba

Relative atomic mass: 137.327 ± 0.007

English: Barium
French: Baryum
Croatian: Barij
German: Barium
Italian: Bario
Spanish: Bario

Atomic number: 56
Group numbers: 2
Period: 6
Standard state (20 °C): solid

Discovery: 1808 Sir Humphry Davy (GB)

Barium was discovered by Sir Humphry Davy (GB) in 1808. The origin of the name comes from the Greek word 'barys' meaning 'heavy'. It is a soft, slightly malleable, silvery-white metal. Barium oxidises in air and reacts with water. Soluble compounds are toxic by ingestion. Barium is found in barytine (BaSO4) and witherite (BaCO3), it is never found in pure form due to its reactivity. Barium must be stored under kerosene to remain pure. Barite, or barium sulfate (BaSO4) is used as a filter for rubber, plastics and resins. It is insoluble in water and so is used in X-rays of the digestive system. Barium nitrate, Ba(NO3)2, burns brilliant green and is used in fireworks.

Electronic configuration: [Xe] 6s²
Formal oxidation number: +2
Atomic radius: 217.4 pm

Electronegativities: 0.89
Thermal conductivity: 18.4 W/(m K)
Electrical resistivity (20 °C): 50 μΩcm

Melting point: 727 °C
Boiling point: 1897 °C

Heat of fusion: 7.66 kJ/mol
Heat of vaporization: 150.9 kJ/mol
Heat of atomization: 180.7 kJ/mol