What is Thallium?

Thallium is a metal belonging to the main Group 13 (IIIa, or boron group) of the periodic table.

What is Thallium?
Table of Contents☰

About Thallium

  • It is globally known as the ‘poisoner’s poison’.
  • It was discovered by Sir William Crookes in 1861.
  • It is a metal belonging to the main Group 13 (IIIa, or boron group) of the periodic table.
  • It was used historically as a rodenticide.
  • Properties
    • It is tasteless and odorless.
    • It is a soft, heavy and low-melting element of low tensile strength.
    • It does not dissolve in water.
    • It dissolves slowly in hydrochloric acid and dilute sulfuric acid and rapidly in nitric acid.
    • It is found in trace amounts in the earth’s crust.
    • This metal continues to oxidize upon prolonged contact with air, generating a heavy nonprotective oxide crust.
  • Trace amounts of thallium are present in sulfide ores of zinc and lead; in the roasting of these ores, the thallium becomes concentrated in the flue dusts, from which it is recovered.
  • Applications: It is used in the manufacture of electronics, low temperature thermometers, optical lenses, and imitation precious jewels. 

Q1) What is a periodic table?

It is a tabular arrangement of chemical elements, organized by their atomic number, electron configuration, and recurring chemical properties. Elements in the periodic table are ordered in rows (periods) and columns (groups).

Source: Scientist kills husband, in-laws: What is Thallium and why murderers use this poison?

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