9 F 18.998

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.