PolyiodideThe polyiodides are a class of polyhalogen anions composed entirely of iodine atoms. The most common and simplest member is the triiodide ion, I3−. Other known larger polyiodides include [I4]2−, [I5]−, [I6]2−, [I7]−, [I8]2−, [I9]−, [I10]2−, [I10]4−, [I11]3−, [I12]2−, [I13]3−, [I14]4-, [I16]2−, [I22]4−, [I26]3−, [I26]4−, [I28]4− and [I29]3−. All these can be considered as formed from the interaction of the I–, I2, and I3− building blocks.
Iodine–starch testThe iodine–starch test is a chemical reaction that is used to test for the presence of starch or for iodine. The combination of starch and iodine is intensely blue-black. The interaction between starch and the triiodide anion (I3-) is the basis for iodometry. The iodine–starch test was first described by J. J. Colin and H. F. Gaultier de Claubry, and independently by F. Stromeyer, in 1814. The triiodide anion instantly produces an intense blue-black colour upon contact with starch.
Potassium iodidePotassium iodide is a chemical compound, medication, and dietary supplement. It is a medication used for treating hyperthyroidism, in radiation emergencies, and for protecting the thyroid gland when certain types of radiopharmaceuticals are used. In the third world it is also used for treating skin sporotrichosis and phycomycosis. It is a supplement used by people with low dietary intake of iodine. It is administered orally. Common side effects include vomiting, diarrhea, abdominal pain, rash, and swelling of the salivary glands.
IodineIodine is a chemical element with the symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , and boils to a violet gas at . The element was discovered by the French chemist Bernard Courtois in 1811 and was named two years later by Joseph Louis Gay-Lussac, after the Ancient Greek Ιώδης 'violet-coloured'. Iodine occurs in many oxidation states, including iodide (I−), iodate (IO3-), and the various periodate anions.
HalogenThe halogens (ˈhælədʒən,ˈheɪ-,-loʊ-,_-ˌdʒɛn) are a group in the periodic table consisting of six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and tennessine (Ts), though some authors would exclude tennessine as its chemistry is unknown and is theoretically expected to be more like that of gallium. In the modern IUPAC nomenclature, this group is known as group (XVII) or group (VII). The word "halogen" means "salt former" or "salt maker".
Oxidation stateIn chemistry, the oxidation state, or oxidation number, is the hypothetical charge of an atom if all of its bonds to other atoms were fully ionic. It describes the degree of oxidation (loss of electrons) of an atom in a chemical compound. Conceptually, the oxidation state may be positive, negative or zero. While fully ionic bonds are not found in nature, many bonds exhibit strong ionicity, making oxidation state a useful predictor of charge. The oxidation state of an atom does not represent the "real" charge on that atom, or any other actual atomic property.
StarchStarch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants for energy storage. Worldwide, it is the most common carbohydrate in human diets, and is contained in large amounts in staple foods such as wheat, potatoes, maize (corn), rice, and cassava (manioc). Pure starch is a white, tasteless and odorless powder that is insoluble in cold water or alcohol. It consists of two types of molecules: the linear and helical amylose and the branched amylopectin.