Fluorine Gas

Fluorine gas is the elemental form of the chemical element fluorine at standard temperature and pressure.

Fluorine gas consists of molecules, rather than atoms of fluorine. Two atoms of fluorineform each molecule of chlorine, hence molecules of chlorine are said to be diatomic and the chemical symbol for fluorine gas is F₂.

Fluorine gas is pale yellow in colour and highly toxic, corrosive, oxidising, and can cause ignition of some organic materials.

Fluorine gas is not found in nature but the element fluorine is present in certain naturally-occuring minerals, such as:

• Cryolite (Na₃AlF₆),
• Fluorite (CaF₂), and
• Fluorapatite 3Ca₃(PO₄)₂.Ca(ClF).

The reason fluorine is not found in its elemental form in nature is its extreme reactivity:
Fluorine is the most reactive of all the elements.

Discovery of Fluorine Gas

The mineral fluorite, which is a natural form of calcium fluoride (and therefore contains the element fluorine), was discussed in a printed article written in 1530 by the German scholar and scientist Georgius Agricola. He called it "fluorspar" and commented on it's usefulness as a flux, which is a chemical cleaning agent used to prepare metal surfaces by removing oxidation from them before they are joined together by soldering, brazing or welding. The earliest known and documented preparation of hydrofluoric acid (HF) was by unknown English glassworker in 1720. Then in 1771, Swedish chemist Carl Wilhelm Scheele obtained impure hydrofluoric acid by heating fluorite with sulphuric acid. Almost anhydrous acid was reported in 1809. In 1811 French physicist André-Marie Ampère suggested that it was a compound of hydrogen and "an unknown element, analogous to chlorine", for which he proposed the name fluorine. Due to the extreme reactivity of fluorine (meaning that it has a high tendency to form compounds with other elements incl. e.g. by chemical reactions that etch any glass with which it comes into contact), the element fluorine was not isolated for another 74 years. In 1886 the French chemist Ferdinand Frederick Henri Moissan (who is often referred to as simply "Henri Moissan") reported success in isolating elemental fluorine gas (F₂), for which he received the Nobel Prize for Chemistry in 1906.
Sadly other chemists had been blinded or killed in their attempts to isolate this highly reactive and dangerous element.

Health effects of Fluorine Gas

Humans can detect the smell of fluorine gas at extremely low concentrations - from only one part in 20 billions.
Not only is fluorine gas highly toxic but soluble fluorides are also moderately toxic. Because fluorine gas is not found in nature and it very quickly reacts with other chemicals to form compounds where is does exist, most people do not encounter fluorine gas in other than trace quantities, if that.

Compounds of the element fluorine also have reported consequences and applications in the fields of health and wellness, e.g.

• Fluoride in Toothpaste and Dentistry - Some inorganic fluoride compounds, e.g. sodium fluoride (NaF), tin(II) fluoride (SnF₂) and sodium monofluorophosphate (Na₂PO₃F) are used in toothpastes to prevent dental cavities.
• Fluoride Poisoning - There have been cases of fluoride poisoning due to accidental ingestion of insecticides or rodenticides containing compounds of fluorine. There have also been reports of fluoride poisonings due to the ingestion of fluoride-containing toothpaste, and concerns expressed about the possible malfunction of water fluoridation equipment.
• Other Health and Medical Uses of fluorine-based compounds - Sodium monofluorophosphate (Na₂PO₃F) is also used in some treatments for the osteoporosis.

Isotopes of Fluorine

Naturally occuring fluorine is monoisotopic, which means that there is only one isotope of natural fluorine.
That isotope is fluorine-19.
As the atomic number of fluorine is 9, there are 9 protons and 19 - 9 = 10 neutrons in each atom of fluorine-19.

Compounds of the radioactive isotope fluorine-18 emit positrons and are sometimes used in positron emission tomography ("PET scanning"), which is a type of medical imaging.

Uses of Elemental Fluorine (Fluorine Gas)

• Plasma Etching in semiconductor manufacturing.
• Flat panel display production and microelectromechanical systems fabrication

For more information about fluorine see the main page about fluorine element.