Thallium
THAL-i-em
Thallium (Tl) is a soft gray metal that has the atomic number 81 in the periodic table in Group 13. It has the symbol Tl.
Thallium was discovered in 1861 by William Crookes> he had been given an ore containing selenium which he extracted leaving behind tellurium. Eleven years later he tried to isolate tellurium again but instead through analysis with spectroscopy realised he had isolated a completely new element. Thalium was named after the Greek word ‘Thallos’ which means green shoot, in reference to its unique green line. Thallium is a highly toxic compound and was used in the Agatha Christie novel ‘the pale horse.’ Thallium is used in rat poison and insecticide and also used to make photovoltaic cells. It is a solid metal at room temperature with a melting point of 304°c and a boiling point of 1473°c.
FAQ's
Sir William Crookes
1861
Uses
Its compounds are used in rat and ant poisons. Also for detecting infrared radiation.
Sources
Found in iron pyrites. Also in crookesite, hutchinsonite and lorandite. Most is recovered from the byproducts of lead and zinc refining.
About the author
Nathan M
Nathan has a degree in BSc Biomedical Chemistry at Warwick University and a degree in PGCE Science at Wolverhampton University, UK. Nathan's subject matter ranges from general chemistry and organic chemistry. Nathan also created the curriculum on Breaking Atom in the course page.
Citation
Tl
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