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F

Fluorine

Fluorine is a chemical element with the symbol F and atomic number 9. It has a standard atomic weight of 18.998, sits in period 2 and group 17, and is classified as a halogen.

Properties

SymbolF
Atomic number9
Standard atomic weight18.998
CategoryHalogen
Group17
Period2
Electron configuration[He] 2s2 2p5
Outer-shell electrons7

The figure of 18.998 is a standard atomic weight.

Compounds containing fluorine

18 of the compounds in this reference contain F, listed by the fraction of their mass it makes up.

CompoundFormulaAtoms% by mass
hydrofluoric acidFH195.0%
nitrogen trifluorideF3N380.3%
sulfur hexafluorideF6S678.0%
fluoriteCaF2248.7%
sodium fluorideFNa145.2%
xenon tetrafluorideF4Xe436.7%
sitagliptinC16H15F6N5O628.0%
fluoxetineC17H18F3NO318.4%
fluconazoleC13H12F2N6O212.4%
ezetimibeC24H21F2NO329.3%
citalopramC20H21FN2O15.9%
midazolamC18H13ClFN315.8%
ciprofloxacinC17H18FN3O315.7%
haloperidolC21H23ClFNO215.1%
dexamethasoneC22H29FO514.8%
risperidoneC23H27FN4O214.6%
rosuvastatinC22H28FN3O6S13.9%
atorvastatinC33H35FN2O513.4%

Calculate with fluorine

Group 17

Atomic weights are the IUPAC 2021 standard values, abridged to the conventional five significant figures. Group, period, category and electron configuration are derived from the atomic number rather than stored, so they cannot drift out of step with it.