Fluorine: the essentials
Fluorine is a Group 17 element. Fluorine is the most electronegative and reactive of all elements. It is a pale yellow, corrosive gas, which reacts with practically all organic and inorganic substances. Finely divided metals, glass, ceramics, carbon, and even water burn in fluorine with a bright flame. It is not uncommon to see fluorine spelled incorrectly as flourine.
Fluorine: historical information
In 1670 a recipe containing Bohemian emerald (now known as calcium fluoride, CaF2) was used to etch glass. It seems that George Gore made a little fluorine through an electrolytic process but his apparatus exploded when the fluorine produced reacted with hydrogen from the other electrode. The element finally was isolated in 1886 by Ferdinand Frederic Henri Moisson who used an apparatus constructed from platinum. His reward was the Nobel Prize for chemistry in 1906.
Fluorine: physical properties
Fluorine: orbital properties
Isolation: it would never be necessary to make fluorine gas in most laboratories. Fluorine is available commercially in cylinders but is very difficult to handle. Fluorine may be recovered with difficulty as a highly reactive and corrosive pale yellow gas by electrolysis of hot molten mixtures (1:2) of potassium fluoride (KF) and hydrogen fluoride (HF). The electrolyte is corrosive, so is the product. Grease must be avoided because of the fire hazard. It is difficult to store as it reacts with most materials but steel and Monel metal containers may be used as the metal surfaces deactivate through the formation of unreactive surface fluorides.