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Fluorapatite as a naturally occurring impurity in apatite generates hydrogen fluoride as a byproduct during the production of phosphoric acid, as apatite is digested by sulfuric acid. The hydrogen fluoride byproduct is now one of the industrial sources of hydrofluoric acid , which in turn is used as a starting reagent for synthesis of a range ...
Apatite is a group of phosphate minerals, usually hydroxyapatite, fluorapatite and chlorapatite, with high concentrations of OH −, F − and Cl − ion, respectively, in the crystal. The formula of the admixture of the three most common endmembers is written as Ca 10 ( PO 4 ) 6 (OH,F,Cl) 2 , and the crystal unit cell formulae of the ...
This page was last edited on 6 October 2007, at 03:35 (UTC).; Text is available under the
Hexafluorosilicic acid is produced commercially from fluoride-containing minerals that also contain silicates. Specifically, apatite and fluorapatite are treated with sulfuric acid to give phosphoric acid, a precursor to several water-soluble fertilizers.
This list includes those recognised minerals beginning with the letter F.The International Mineralogical Association is the international group that recognises new minerals and new mineral names; however, minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date.
Hydroxyapatite (IMA name: hydroxylapatite [5]) (Hap, HAp, or HA) is a naturally occurring mineral form of calcium apatite with the formula Ca 5 (PO 4) 3 (OH), often written Ca 10 (PO 4) 6 (OH) 2 to denote that the crystal unit cell comprises two entities. [6] It is the hydroxyl endmember of the complex apatite group.
Mineral symbols (text abbreviations) are used to abbreviate mineral groups, subgroups, and species, just as lettered symbols are used for the chemical elements.. The first set of commonly used mineral symbols was published in 1983 and covered the common rock-forming minerals using 192 two- or three-lettered symbols. [1]
The process is reversible as saliva supplies back OH − to reform apatite. If fluoride, F −, ions are present in saliva, fluorapatite, Ca 5 (PO 4) 3 F, also forms. Ca 5 (PO 4) 3 + (aq) + F − (aq) → Ca 5 (PO 4) 3 F (s) Fluorapatite resists attacks by acids better than apatite itself, so the tooth enamel resists decay better than enamel ...