What is Iodine?
Iodine (from the Greek word Iodes, meaning "violet"), is a chemical element in the periodic table that has the symbol I and atomic number 53. Chemically, iodine is the least reactive of the halogens, and the most electropositive halogen after astatine. Iodine is primarily used in medicine, photography and dyes. It is required in trace amounts by most living organisms.
As with all other halogens (members of Group VII in the Periodic Table), iodine forms diatomic molecules, and hence, has the molecular formula of I2.
Iodine is a dark-gray/purple-black solid that sublimates at standard temperatures into a purple-pink gas that has an irritating odor. This halogen forms compounds with many elements, but is less active than the other members of its Group VII (halogens) and has some metallic-like properties. Iodine dissolves easily in chloroform, carbon tetrachloride, or carbon disulphide to form purple solutions (It is only slightly soluble in water, giving a yellow solution). The deep blue color of starch-iodine complexes is produced only by the free element.
Many students who have seen the classroom demonstration where iodine crystals are gently heated in a test tube come away with the impression that liquid iodine cannot exist at atmospheric pressure. This misconception arises because sublimation occurs without the intermediacy of liquid. The truth is that if iodine crystals are heated carefully to their melting point of 113.7 °C, the crystals will fuse into a liquid, which will be present under a dense blanket of the vapor.
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Relevant sites for Iodine:
Organic Iodine(I, III, and V) Chemistry: 10 Years of Development ...
A full list of our papers dealing with the organic iodine(I, ... So far, nine organic iodine(III) compounds have been used as the oxidants for the oxidative ...
International Union of Pure and Applied Chemistry
In addition, marine plants and animals have provided a rich source of varied and unexpected organic iodine compounds that occur, along with other organic ...
Chemistry and the Aquarium
These results are indicative of total iodine (iodide + iodate + organic iodine) ... Dissolved organic iodine in marine waters: Determination, occurrence and ...
Iodine chemistry and its role in halogen activation and ozone loss ...
Other aqueous-phase species are only temporary reservoirs and can be re-activated to yield gas phase iodine. Assuming release rates of the organic iodine ...
Potassium iodide - Wikipedia, the free encyclopedia
KI is often used as a source of iodide ion in organic synthesis. A useful application is in the preparation of aryl iodides from arenediazonium salts[5], ...
Iodine: The Universal Nutrient Article
“When I was a medical student, iodine in the form of KI was the universal medicine. ... it was incorporated into the toxic organic iodine-containing drugs. ... |
