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Thorium (Th): Fun Facts and Information About the Element


What is the symbol? Th
What is the atomic number? 90
What is the atomic weight? 232.0381
What is the melting point in Celsius? 1750
What is the boiling point in Celsius? 4790
What is the density (g/cm3)? 11.72
What year was it discovered? 1829
Who discovered the element? Jöns Jacob Berzelius
What group is the element in? 102
What is the electron configuration? [Rn] 6d2 7s2
What is the ionization energy? 6.3067
What element category is it in? Actinoids

Where is Thorium Found?

Large deposits of thorium minerals have been reported in New England and elsewhere, but these have not yet been exploited. Thorium is recovered commercially from the mineral monazite, which contains from 3 to 9% ThO2 along with rare-earth minerals.

What is Thorium Used For?

The metal is a source of nuclear power. Work has been done in developing thorium cycle converter-reactor systems. Several prototypes, including the HTGR and MSRE, have operated. HTGR reactors are not expected to become important commercially for many years because of certain operating difficulties.