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Several elements show their highest oxidation state only in a few compounds, one of which is the fluoride; and some elements' highest known oxidation state is seen exclusively in a fluoride. For groups 1–5, 13–16 (except nitrogen), the highest oxidation states of oxides and fluorides are always equal.
Aluminium monofluoride, also known as fluoridoaluminium, is the chemical compound with the formula AlF. This elusive species is formed by the reaction between aluminium trifluoride and metallic aluminium at elevated temperatures but quickly reverts to the reactants when cooled. [ 1 ]
Most fluorine exists as fluoride-containing minerals. Fluorite, fluorapatite and cryolite are the most industrially significant. [61] [63] Fluorite (CaF 2), also known as fluorspar, abundant worldwide, is the main source of fluoride, and hence fluorine. China and Mexico are the major suppliers.
1. Tomatoes. The high acidity in tomatoes can react strongly with aluminum, causing tiny bits of metal to leach into the food. While this can impart that gross metallic taste, the bigger issue is ...
The majority of aluminium fluoride is produced by treating alumina with hydrogen fluoride at 700 °C: [4] Hexafluorosilicic acid may also be used make aluminium fluoride. [11] H 2 [SiF 6] + Al 2 O 3 + 3 H 2 O → 2 AlF 3 + SiO 2 + 4 H 2 O. Alternatively, it is manufactured by thermal decomposition of ammonium hexafluoroaluminate. [12]
All vegetation contains some fluoride, which is absorbed from soil and water. [10] Some plants concentrate fluoride from their environment more than others. All tea leaves contain fluoride; however, mature leaves contain as much as 10 to 20 times the fluoride levels of young leaves from the same plant. [18] [19] [20]
Although hydrogen fluoride may appear to be an unlikely nucleophile, it is the most common source of fluoride in the synthesis of organofluorine compounds. Such reactions are often catalysed by metal fluorides such as chromium trifluoride. 1,1,1,2-Tetrafluoroethane, a replacement for CFC's, is prepared industrially using this approach: [18]
The CDC calls the practice of adding fluoride to tap water systems one of the 10 greatest public health achievements of the last century.