Element 9
Fluorine
Halogens
Fluorine (F) is in the p-block of the periodic table — group 17, period 2.
Fluorine is a chemical element with symbol F and atomic number 9.
Key data
- Atomic number
- 9
- Atomic mass
- 18.998 u
- Group / Period
- 17 / 2
- Block
- p-block
- Phase at STP
- Gas
- Density
- 1.696 g/cm³
- Melting point
- -219.7 °C
- Boiling point
- -188.1 °C
- Electron configuration
- [He] 2s2 2p5
Periodic table block
Fluorine is in the p-block (group 17, period 2). Elements land in the p-block when their highest-energy electrons fill a p subshell — this region holds most nonmetals, the metalloids, and the metals on the right of the table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •Toothpaste
- •Teflon coatings
- •Refrigerants
Discovery
Year: 1886
Discovered by: André-Marie Ampère
Named by: Humphry Davy
Frequently asked questions
What is the atomic number of Fluorine?
Fluorine has atomic number 9. Its symbol is F and its atomic mass is 18.998 u.
What category of element is Fluorine?
Fluorine is classified as halogens. It sits in group 17, period 2 of the periodic table.
What block of the periodic table is Fluorine in?
Fluorine is in the p-block (group 17, period 2). Its highest-energy electrons occupy the p subshell — you can see this in its electron configuration, [He] 2s2 2p5.
What is Fluorine used for?
Common uses of Fluorine include: Toothpaste, Teflon coatings, Refrigerants.
When was Fluorine discovered?
Fluorine was discovered in 1886 by André-Marie Ampère.
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