Thorium - ASCII Periodic Table of the Elements

ASCII PERIODIC TABLE OF THE ELEMENTS

  Th

Relative atomic mass: 232.03806 ± 0.00002

English: Thorium
French: Thorium
Croatian: Torij
German: Thorium
Italian: Torio
Spanish: Torio

Atomic number: 90
Group numbers: 3
Period: 7
Standard state (20 °C): solid

Discovery: 1828 Jöns Jacob Berzelius (SE)

Thorium was discovered by Jöns Jacob Berzelius (SE) in 1828. Named after 'Thor', the mythological Scandinavian god of war. It is a heavy, grey, soft, malleable, ductile, radioactive metal that tarnishes in air and reacts with water. It reacts violently with oxidants. Thorium is found in various minerals like monazite and thorite. It is used in making strong alloys, in ultraviolet photoelectric cells. It is a common ingredient in high-quality lenses. When bombarded with neutrons thorium creates uranium-233, a nuclear fuel.

Electronic configuration: [Rn] 6d² 7s²
Formal oxidation number: +4
Atomic radius: 179.8 pm

Electronegativities: 1.3
Thermal conductivity: 54 W/(m K)
Electrical resistivity (20 °C): 13 μΩcm

Melting point: 1750 °C
Boiling point: 4788 °C

Heat of fusion: 19.2 kJ/mol
Heat of vaporization: 513.67 kJ/mol
Heat of atomization: 598.65 kJ/mol