Thallium

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General Properties
Atomic number 81
Atomic mass 204.38amu
Atomic radius 156pm
Electron Configuration [Xe] 4f14 5d10 6s2 6p1
Density 11.8g/cm3
Melting point 304°C
Boiling point 1473°C
First discovered/ developed 1861
Most common compound on Earth Impurities in FeS2 (Iron pyrite)

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Description and uses

Thallium is the 81st element of the periodic table. It was discovered in 1861 by William Crookes who analysed the spectroscopy of a sample of impure sulfuric acid. Thallium has been used for decades as a poison, as its symptoms are very generic, including vomiting and abdominal pain.

Due to its toxicity, it has few commercial uses.

Thallium only has two naturally occurring isotopes. 205Tl is more abundant, with an abundance of around 70%, whereas 203Tl is less abundant, with an abundance of around 30%.

T&C