Fluorine is the first element in Group 17 of the periodic table and the first member of the halogen family. Its atomic number is 9, its atomic mass is 18.998404, and its chemical symbol is F.

Properties

Fluorine is a pale yellow gas with a density of 1.695 grams per cubic centimeter, about 1.3 times that of air. Fluorine's boiling point is -306.6°F (-188.13°C) and its freezing point is -363.3°F (-219.61°C). Fluorine has a strong and characteristic odor that can be detected in amounts as low as 20 parts per billion.

Fluorine is the most reactive of all elements. It combines easily and even explosively with every other element except helium, neon, and argon. It also reacts violently with most compounds and, for this reason, must be handled with great care.

Occurrence and Extraction

Fluorine never occurs as an element in nature, but is found in...