Search results
Results from the WOW.Com Content Network
Fluorine. cubic. Fluorine is a chemical element; it has symbol F and atomic number 9. It is the lightest halogen [note 1] and exists at standard conditions as pale yellow diatomic gas. Fluorine is extremely reactive as it reacts with all other elements except for the light inert gases.
Fluorine compounds typically have a fast NMR relaxation, which enables the use of fast averaging to obtain a signal-to-noise ratio similar to hydrogen-1 NMR spectra. [25] Fluorine-19 is commonly used in NMR study of metabolism, protein structures and conformational changes. [26]
Fluorine is a relatively new element in human applications. In ancient times, only minor uses of fluorine-containing minerals existed. The industrial use of fluorite, fluorine's source mineral, was first described by early scientist Georgius Agricola in the 16th century, in the context of smelting. The name "fluorite" (and later "fluorine ...
Fluorine compounds. Fluorine forms a great variety of chemical compounds, within which it always adopts an oxidation state of −1. With other atoms, fluorine forms either polar covalent bonds or ionic bonds. Most frequently, covalent bonds involving fluorine atoms are single bonds, although at least two examples of a higher order bond exist. [2]
Fluorite (CaF 2), also called fluorspar, is the main source of commercial fluorine. Fluorite is a colorful mineral associated with hydrothermal deposits. It is common and found worldwide. China supplies more than half of the world's demand and Mexico is the second-largest producer in the world. [citation needed] The United States produced most ...
Isotopes of fluorine (9F) ). Only fluorine-19 is stable and naturally occurring in more than trace quantities; therefore, fluorine is a monoisotopic and mononuclidic element. ; it has a half-life of 109.734 (8) min. All other fluorine isotopes have half-lives of less than a minute, and most of those less than a second.
It is used to make most fluorine-containing compounds; examples include the commonly used pharmaceutical antidepressant medication fluoxetine (Prozac) and the material PTFE (Teflon). Elemental fluorine is produced from it. It is commonly used to etch glass and silicon wafers.
Fluorite mining (the main source of fluorine) was estimated in 2003 to be a $550 million industry, extracting 4.5 million tons per year. [4] Mined fluorite is separated into two main grades, with about equal production of each. Acidspar is at least 97% CaF 2; metspar is much lower purity, 60–85%.