Iodine
EYE-eh-dine
Iodine (I) is a purple grey solid non metal. It has the atomic number 53 in the periodic table. It is located in Group 17, the Halogens. It has the symbol I.
Iodine was discovered in 1811 by Bernard Courtois when he was trying to extract potassium chloride from seaweed. By adding sulphuric acid a purple vapour was produced which formed into dark crystals. This was the element Iodine. Iodine’s name comes from the Greek word ‘Iodes’ meaning purple. Iodine easily forms compounds with group 1 and 2 elements usually uncoloured compounds and is one of the least reactive Halogens. Iodine is used in medicine, it is used as a disinfectant in surgery and also in the treatment of the thyroid. Silver iodide is used widely in photography and potassium iodide to clean wounds. In nature Iodine occurs mainly in seawater and seaweed a big source of Iodine for commercial use. It is located in Group 17 as a non metallic solid. It has a melting point of 113°c and a boiling point of 184°c.
FAQ's
Bernard Courtois
1811
Uses
Required in small amounts by humans. Once used as an antiseptic, but no longer due to its poisonous nature.
Sources
Occurs on land and in the sea in sodium and potassium compounds.
About the author
Nathan M
Nathan has a degree in BSc Biomedical Chemistry at Warwick University and a degree in PGCE Science at Wolverhampton University, UK. Nathan's subject matter ranges from general chemistry and organic chemistry. Nathan also created the curriculum on Breaking Atom in the course page.
Citation
I
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