Iodine Periodic Table

Mar 03, 2021 Periodic table, in chemistry, the organized array of all the chemical elements in order of increasing atomic number. When the elements are thus arranged, there is a recurring pattern called the ‘periodic law’ in their properties, in which elements in the same column (group) have similar properties.

Halogen, any of the six nonmetallic elements that constitute Group 17 (Group VIIa) of the periodic table. The halogen elements are fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and tennessine (Ts). Learn more about the properties of halogens in this article. Technical data for Iodine. Click here to buy a book, photographic periodic table poster, card deck, or 3D print based on the images you see here! A sealed sphere of Iodine crystals. Purity is 99.99%. The sphere has beautiful crystals of pure Iodine grown on the inside surface. This makes for a beautiful display sample of this element. Iodine compounds are important in organic chemistry and very useful in medicine. A solution containing potassium iodide and iodine in alcohol is used to disinfect external wounds. Silver iodide is a major ingredient to traditional photographic film. Iodine is added to table salt to prevent thyroid disease.

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Karl ChristeSee All Contributors

Ptable Periodic Table

Research Professor of Chemistry, Department of Chemistry, University of Southern California, Los Angeles, Calif.
Alternative Title: I

Find port of ip address. Iodine (I), chemical element, a member of the halogen elements, or Group 17 (Group VIIa) of the periodic table.

Periodic Table of the Elements
Test your bond with the periodic table of elements in this quiz on all 118 chemical elements and their symbols. You may be familiar with the chemical symbols for hydrogen and oxygen, but can you match such lower-profile elements as gadolinium and erbium with their corresponding symbols?
Element Properties
atomic number53
atomic weight126.9044
melting point113.5 °C (236 °F)
boiling point184 °C (363 °F)
specific gravity4.93 at 20 °C (68 °F)
oxidation states−1, +1, +3, +5, +7
electron configuration2-8-18-18-7 or (Kr)5s24d105p5


In 1811 the French chemist Bernard Courtois obtained a violet vapour by heating seaweed ashes with sulfuric acid as a by-product of the manufacture of saltpetre. This vapour condensed to a black crystalline substance, which he called “substance X.” In 1813 British chemist Sir Humphry Davy, who was passing through Paris on his way to Italy, recognized substance X as an element analogous to chlorine; he suggested the name iodine from the Greek word ioeides, “violet coloured.”

Iodine Periodic Table Information

Occurrence and distribution

Iodine is never found in nature uncombined, and it is not concentrated sufficiently to form independent minerals. It is present in seawater, but sparingly, as the iodide ion, I, to the extent of approximately 50 mg per metric ton (0.0016 ounce per ton) of seawater. It is also formed in seaweeds, oysters, and cod livers. Sodium iodate (NaIO3) is contained in crude Chilesaltpetre (sodium nitrate, NaNO3). The human body contains iodine in the compoundthyroxine, which is produced in the thyroid gland.

The only naturally occurring isotope of iodine is stable iodine-127. An exceptionally useful radioactive isotope is iodine-131, which has a half-life of eight days. It is employed in medicine to monitor thyroid gland functioning, to treat goitre and thyroid cancer, and to locate tumours of the brain and of the liver. It is also used in investigations to trace the course of compounds in metabolism. Several iodine compounds are used as contrast mediums in diagnostic radiology. In aqueous solution even minute amounts of iodine in the presence of starch produce a blue-black colour.

Iodine Periodic Table Letter



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Iodine Periodic Table Of Elements

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