Fluorine
Reactive Nonmetal
Fluorine (F) is a chemical element with atomic number 9, classified as a reactive nonmetal. At room temperature it is a gas. It was discovered in 1886 by Henri Moissan.
Properties
- Atomic number
- 9
- Atomic mass
- 18.998 u
- Category
- Reactive Nonmetal
- Group
- 17
- Period
- 2
- Block
- p-block
- Electron configuration
- [He] 2s² 2p⁵
- Phase at STP
- Gas
- Density
- 1.696 g/L
- Melting point
- 53.53 K (-219.6 °C)
- Boiling point
- 85.03 K (-188.1 °C)
- Electronegativity
- 3.98
- Atomic radius
- 42 pm
- Ionization energy
- 17.423 eV
- Discovery
- 1886 · Henri Moissan
Common uses
Toothpaste, Teflon, refrigerants, uranium enrichment
Did you know?
Most electronegative element - attacks almost everything including glass.
Compounds you can make with fluorine
Fluorine appears in 6 compounds in our periodic table sandbox. Each one is a real substance with its true chemical formula — combine the right elements in the right ratio below to discover it.
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HF
Hydrogen Fluoride
Forms hydrofluoric acid, uniquely able to dissolve glass.
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CaF2
Calcium Fluoride (Fluorite)
The mineral fluorite, a source of fluorine and used in optics.
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BF3
Boron Trifluoride
A useful industrial catalyst with a flat, triangular shape.
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NaF
Sodium Fluoride
Added to toothpaste and drinking water to strengthen tooth enamel.
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UF6
Uranium Hexafluoride
The volatile uranium compound fed into centrifuges to enrich nuclear fuel.
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KrF2
Krypton Difluoride
A rare compound of a "noble" gas, only stable when kept extremely cold.