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Fluoride is classified as a weak base since it only partially associates in solution, but concentrated fluoride is corrosive and can attack the skin. Fluoride is the simplest fluorine anion. In terms of charge and size, the fluoride ion resembles the hydroxide ion.
The fluorine–fluorine bond of the difluorine molecule is relatively weak when compared to the bonds of heavier dihalogen molecules. The bond energy is significantly weaker than those of Cl 2 or Br 2 molecules and similar to the easily cleaved oxygen–oxygen bonds of peroxides or nitrogen–nitrogen bonds of hydrazines. [8]
Fluorine is the 13th most abundant element in Earth's crust at 600–700 ppm (parts per million) by mass. [61] Though believed not to occur naturally, elemental fluorine has been shown to be present as an occlusion in antozonite, a variant of fluorite. [62] Most fluorine exists as fluoride-containing minerals.
Fluoride, the chemical ion of the mineral fluorine, ... But a fluoride level of above 1.5 mg/L is found in wells and community water systems that serve over 2.9 million people in the U.S ...
PET scan using fluorine-18. Fluorine may interact with biological systems in the form of fluorine-containing compounds. Though elemental fluorine (F 2) is very rare in everyday life, fluorine-containing compounds such as fluorite occur naturally as minerals. Naturally occurring organofluorine compounds are extremely rare. Man-made fluoride ...
The electrowinning of aluminium relies on the electrolysis of aluminium fluoride in molten cryolite. Several kilograms of HF are consumed per ton of Al produced. Other metal fluorides are produced using HF, including uranium tetrafluoride. [14] HF is the precursor to elemental fluorine, F 2, by electrolysis of a solution of HF and potassium ...
As indicated throughout this article, fluorine-substituents lead to reactivity that differs strongly from classical organic chemistry. The premier example is difluorocarbene, CF 2, which is a singlet whereas carbene (CH 2) has a triplet ground state. [12] This difference is significant because difluorocarbene is a precursor to tetrafluoroethylene.
The fluoride opposition argues there has never been a double-blinded, randomized, controlled clinical trial — the gold standard of scientific research — looking at the effects of fluoride on ...