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iodine (I)

Term: iodine (I)
Literally meaning: “pertaining  to purple”
Origin: Anc Greek
οειδής/ ioeides (=purple, violet) because of the color of elemental iodine vapor.
[<αρχ. ώδης < ον= 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.
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.

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