← Periodic Table
9
p
F
18.9980

Fluorine

Halogen

Atomic Properties

Atomic Number
9
Atomic Mass
18.9980 u
Electron Configuration
[He] 2s2 2p5
Electronegativity
3.98
Block
p-block
Group
17
Period
2

🌡 Physical Properties

Phase (STP)
gas
Melting Point
53.48 K
Boiling Point
85.03 K
Density
0.0017 g/cm³

About Fluorine

Most electronegative element; used in toothpaste and Teflon.

🔬 Isotopes of Fluorine

Fluorine has 1 naturally occurring isotope.

IsotopeMass NumberAtomic Mass (u)AbundanceType
19F1918.99840316100.00%Stable

Data source: NIH PubChem (aggregated from IUPAC, NIST)