Fluorine
Fluorine is a chemical element with symbol F and atomic number 9. It is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. As the most electronegative element, it is extremely reactive:almost all other elements, including some noble gases, form compounds with fluorine.
About the element
Overview
Fluorine is a chemical element with symbol F and atomic number 9. It is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. As the most electronegative element, it is extremely reactive:almost all other elements, including some noble gases, form compounds with fluorine.
From the glossary modal
Element Snapshot
Key data
Properties
| Property | Value |
|---|---|
| Atomic Number | 9 |
| Symbol | F |
| Atomic Mass | 18.9984031636 u |
| Category | Halogen |
| State at STP | Gas |
| Electronegativity | 3.98 |
| Density | 1.696 g/cm³ |
| Melting Point | 53.48 K |
| Boiling Point | 85.03 K |
Atomic structure
Electron Configuration
History
Discovery
Common questions
Frequently Asked Questions
Fluorine has atomic number 9.
Fluorine is classified as Halogen.
Fluorine is Gas at standard temperature and pressure.