Thallium [Tl] (CAS-ID: 7440-28-0) locate me
An: 81 N: 123 Am: 204.3833
Group No: 13  Group Name: (none)
Block: p-block  Period: 6
State: solid at 298 K
Colour: silvery white Classification: Metallic
Boiling Point: 1746K (1473'C)
Melting Point: 577K (304'C)
Density: 11.85g/cm3
Shell Structure diagram | Atomic Radius diagram
Isotopes | More Info
Discovery Information
Who: Sir William Crookes
When: 1861
Where: England
Name Origin
Greek: thallos (young shoot) from a bright-green line in its spectrum.
Sources
Found in iron pyrites. Also in the minerals crookesite, hutchinsonite and lorandite. It is found in the Earth's crust at a concentration estimated to be 0.6mg/kg.
Uses
Its compounds were used in rat and ant poisons, but this use is no longer allowed in many countries due to safety concerns. Also for in gamma radiation detecting equipment, detecting infrared radiation and heart muscle research.
Notes
This metal is very soft and malleable and can be cut with a knife.
Thallium and its compounds are highly toxic and should be handled with great care. Thallium is a suspected human carcinogen.
Thallium was once an effective murder weapon before its effects became understood and an antidote (prussian blue) discovered.
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