Element #9

Fluorine

halogen gas Discovered 1886

18.998 Atomic Mass (u)

-219.67 C Melting Point

-188.11 C Boiling Point

0.001553 g/cm3 Density

3.98 Electronegativity

[He] 2s2 2p5 Electron Config

2 Period

17 Group

📖 About Fluorine

The most electronegative and reactive of all elements. It reacts violently with almost every substance including many noble gases. Fluorine is so reactive it corrodes glass. Uranium hexafluoride (UF6), used in uranium enrichment, relies on fluorine. Teflon (PTFE) is a fluorocarbon polymer prized precisely because the C-F bond is so strong nothing reacts with it.

🔧 Uses and Applications

Uranium enrichment (as UF6 gas)
Non-stick coatings (Teflon/PTFE)
Toothpaste (fluoride prevents tooth decay)
Refrigerants (HFCs)
Semiconductors etching

💡 Did You Know?

Fact: Fluorine killed or injured many chemists before Henri Moissan finally isolated it in 1886, winning the Nobel Prize. It had been called the "fiend element" due to the difficulty and danger of working with it.