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Thulium (Tm): Fun Facts and Information About the Element

What is the symbol? Tm
What is the atomic number? 69
What is the atomic weight? 168.9342
What is the melting point in Celsius? 1545
What is the boiling point in Celsius? 1727
What is the density (g/cm3)? 9.32
What year was it discovered? 1879
Who discovered the element? Per Theodor Cleve
What group is the element in? 101
What is the electron configuration? [Xe] 4f13 6s2
What is the ionization energy? 6.1843
What element category is it in? Lanthanoids

Where is Thulium Found?

Thulium can be isolated by reduction of the oxide with lanthanum metal or by calcium reduction of a closed container.

What is Thulium Used For?

Because of the relatively high price of the metal, thulium has not yet found many practical applications. 171Tm is potentially useful as an energy source.