An Overview about the Chemical Element Fluorine


Symbol: F

Atomic Number: 9

Atomic Mass: 18.998404 amu (atomic mass units)

Melting Point: minus 219.62 C (53.530006 K, minus 363.31598 F)

Boiling Point: minus 188.14 C (85.01 K, minus 306.652 F)

Number of Protons: 9

Number of Electrons: 9

Number of Neutrons: 10

Classification: Non Metal

Group Name: Halogen

Crystal Structure: Cubic

Density @ 293 K: 0.001696 grams per cubic centimeter

Color: Green

The compound fluorspar was mentioned by Georigius Agricola in1527 as being used as a flux and the name fluorine comes from the Latin “fluere” meaning flow or flux. The next mention of a fluorine compound was in 1670 when a description of glass etching was made which used fluorspar treated with acid.

Chemists had a problem producing the element as it is so reactive no other element could replace it in a compound. George Gore produced a small amount by electrolysis in 1869 but it immediately reacted with the hydrogen being released at the other electrode and his equipment exploded.

The first successful non-explosive production of the pure element was made by the French chemist Ferdinand Frederic Henri Moissan in 1886. He isolated the fluorine gas from the hydrogen gas in when he used electrolysis on potassium fluoride and hydrofluoric acid. The equipment used by Moissan was made entirely out of platinum. His achievement was rewarded with the Noble Prize for Chemistry in 1906.

Fluorine will react with just about any other chemical even water will burn in the gas. It will form compounds with the noble gases xenon, krypton and radon which were previously thought to be inert. The gas is highly toxic.

There is one stable isotope fluorine-19 as well as fifteen unstable isotopes. Fluorine-15 has the shortest half life at 45.71 ento-seconds (an ento-second is ten to the power of minus 21 of a second).

Industrial production of fluorine was not required until the Second World War. The development of the atomic bomb required separation of the isotopes of uranium. Uranium hexafluoride was used for this separation so industrial production of the gas was required. In addition to the fractioning of uranium for the nuclear industry fluorine compounds have a number of uses.

* Fluorides are added to some water supplies to prevent tooth decay. They are also included in toothpastes.

* Hydrofluoric acid it used to etch the glass used in light bulb manufacture.

* Fluoro-chloro hydrocarbons were used extensively in refrigeration and air conditioning units as well as aerosol cans. These chemicals have an adverse effect on the ozone layer so their use is being discontinued.