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Thallium (Tl): Fun Facts and Information About the Element


What is the symbol? Tl
What is the atomic number? 81
What is the atomic weight? 204.3833
What is the melting point in Celsius? 303
What is the boiling point in Celsius? 1457
What is the density (g/cm3)? 11.85
What year was it discovered? 1861
Who discovered the element? Sir William Crookes
What group is the element in? 13
What is the electron configuration? [Xe] 4f14 5d10 6s2 6p1
What is the ionization energy? 6.1082
What element category is it in? Other Metals

Where is Thallium Found?

Thallium occurs in crooksite, lorandite, and hutchinsonite. It is also obtained from the smelting of lead and zinc ores. Manganese nodules, found on the ocean floor, contain thallium.

What is Thallium Used For?

Thallium sulfate has been widely employed as a rodenticide and ant killer. Thallium bromide-iodide crystals have been used as infrared optical materials. Thallium oxide has been used to produce glasses with a high index of refraction, and is used in the manufacture of photo cells. Thallium has been used in treating ringworm and other skin infections.