Fluorine
Fluorine (氟, symbol F) is chemical element number 9, a Halogen in period 2, group 17 of the periodic table, with a standard atomic weight of about 18.998. Most electronegative element. Pale yellow gas, highly reactive and dangerous in elemental form.
Properties
| Atomic number | 9 |
|---|---|
| Symbol | F |
| Atomic mass | 18.998 u |
| Category | Halogen |
| Period | 2 |
| Group | 17 |
| Electron configuration | [He] 2s² 2p⁵ |
| Electronegativity | 3.98 |
| Covalent radius | 57 pm |
| Density | 0.001696 g/cm³ |
| Melting point | 53.53 K |
| Boiling point | 85.03 K |
| Discovery | Henri Moissan, 1886 |
Overview
Most electronegative element. Pale yellow gas, highly reactive and dangerous in elemental form. Element 9, Fluorine (F), is a Halogen found in period 2, group 17. As a halogen it is a reactive nonmetal that readily gains one electron to form a −1 ion.
It has the configuration [He] 2s² 2p⁵ and an electronegativity near 3.98; its 7 outer-shell electrons drive its bonding. Under standard conditions it exists as a gas (a very low melting point); it melts near 53.53 K (-219.6 °C), boils near 85.03 K (-188.1 °C), has a density around 0.001696 g/cm³.
It is widely used in Industrial Gas and Medical / Pharma. On the safety side, it carries a high hazard rating. It was first described by Henri Moissan in 1886. The periodic trends guide explains the underlying patterns.
Electron shells
Electrons per shell: 2 · 7
Main uses
- Industrial Gas
- Medical / Pharma
Hazard
Compounds containing Fluorine
No compounds in this knowledge base contain Fluorine yet.
Data sources
Atomic mass uses IUPAC (CIAAW) standard atomic weights; the covalent radius is from Cordero et al. (2008). Verify on the RSC Periodic Table, PubChem and Wikipedia. Educational reference only.