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Thallium

Post-Transition Metal
Atomic Mass
204.38 u
Density
11.85 g/cm³
Melting Point
304 °C
Boiling Point
1,457 °C
State
Solid
Discovery
1861

Discovery

Discovered by William Crookes in 1861.

Common Uses

  • Used in the production of infrared detectors and in some types of glass.
  • Used as a component in semiconductors.
  • Historically used in rat poisons and pesticides.

Interesting Facts

  • Thallium is highly toxic and has few practical uses due to its dangerous properties.
  • It is soft and can be cut with a knife.
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