Term: iodine (I)
Literally
meaning: “pertaining
to purple”
Origin: Anc Greek
ἰοειδής/
ioeides (=purple, violet) because of the color of elemental iodine vapor.
[<αρχ. 'éώδης < /éον= violete (flower)
Coined/History
Iodine was discovered in 1811 by French chemist Bernard Courtois (1777-1838).
The element was derived during Napoleonic wars (1804-1815), from saltpeter production which
was used to make gunpowder. Courtois who made saltpeter from the ashes of seaweed, once added excessive sulfuric acid and a cloud
of purple vapor rose which crystallized on cold surfaces forming dark crystalls.
Courtois gave the samples to his friend Charles Bernard Desormes (1777-1862)
and Nicolas Clement (1779-1841) who made
public this discovery. He also gave some of the substance to chemist Joseph
Louis Gay-Lussac (1778-1850) who suggested the name “iodine”. Unfortunatelly,
although Courtois continued to produce and sell iodine, he died in poverty.
In 1819 Jean-Baptiste Dumas proved that
sponges used for many years to treat goiter contained iodine. In the mid-1800s,
French agricultural chemist Jean Boussingault first suggested that iodine
compounds might be able to cure goiter. Boussingault found iodine in the salts
and suggested the cure, but it was not until 1896 that this treatment was
confirmed. Ther Austrian psychiatrist Julius Wagner von Jaurreg (1857-1940)
established that goiter could be prevented by taking iodine tablets regularly.
Definition
Iodine is a chemical element with atomic mass
126.90447 and atomic number 53. It is belongs to halogen group which also
includs fluorine, chlorine, bromine and
astatine. Most plants and animals requires iodine for a proper growth in small
quantities. Main sources of iodine are fish and shellfish from the sea. Iodine is not found in nature as it is always
combined with other elements. Pure iodine is poisonous.
No comments:
Post a Comment