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30-Jul-2017 18:03

For work with fluorine at temperatures up to 600 °C (1,100 °F), Monel is suitable; sintered alumina is resistant up to 700 °C (1,300 °F).

When lubricants are required, fluorocarbon oils are most suitable.

He used K), both of which can be easily prepared from HF solutions.

The high oxidizing power of fluorine allows the element to produce the highest oxidation numbers possible in other elements, and many high oxidation state fluorides of elements are known for which there are no other corresponding halides—e.g., silver difluoride (Ag F), composed of two fluorine atoms, combines with all other elements except helium and neon to form ionic or covalent fluorides.

Fluorine (F), most reactive chemical element and the lightest member of the halogen elements, or Group 17 (Group VIIa) of the periodic table.

Its chemical activity can be attributed to its extreme ability to attract electrons (it is the most electronegative element) and to the small size of its atoms.fluorite) was described in 1529 by the German physician and mineralogist Georgius Agricola.

The difficulty in handling the element and its toxic properties contributed to the slow progress in fluorine chemistry.

For more than 150 years, all chemical methods had failed to produce the element, success having been achieved only by the use of electrolytic methods. Christe reported the first chemical preparation of fluorine, where “chemical preparation” means a method that does not use techniques such as electrolysis, photolysis, and discharge or use fluorine itself in the synthesis of any of the starting materials.

(With appropriate precautions, the element itself may be used for the fluorination of organic compounds.) Sulfur hexafluoride is used as a gaseous electrical insulator.

Elemental fluorine, often diluted with nitrogen, reacts with hydrocarbons to form corresponding fluorocarbons in which some or all hydrogen has been replaced by fluorine.

Fluorine reacts violently with organic matter (such as rubber, wood, and cloth), and controlled fluorination of organic compounds by the action of elemental fluorine is only possible if special precautions are taken.

Fluorspar is the most important source of fluorine.

Some metals, such as nickel, are quickly covered by a fluoride layer, which prevents further attack of the metal by the element.