Search results
Results from the WOW.Com Content Network
The fluorine–fluorine bond of the difluorine molecule is relatively weak when compared to the bonds of heavier dihalogen molecules. The bond energy is significantly weaker than those of Cl 2 or Br 2 molecules and similar to the easily cleaved oxygen–oxygen bonds of peroxides or nitrogen–nitrogen bonds of hydrazines. [8]
Its use began in the 1940s, following studies of children in a region where water is naturally fluoridated. It is now used widely in public water systems in the United States and some other parts of the world, such that about two-thirds of the U.S. population is exposed to fluoridated water supplies [5] and about 5.7% of people worldwide. [6]
Perfluorocarbons (PFCs) are the compounds consisting of fluorine and carbon. They are widely used in the electronics, cosmetics, and pharmaceutical industries, as well as in refrigeration when combined with other gases. PFCs were commonly used as fire extinguishants in the past and are still found in older fire protection systems.
The use of salts of cationic nitrogen increases the rates and yields of electrophilic fluorination, because the cationic nitrogen removes electron density from fluorine. N-fluoropyridinium ions and iminium ions can also be used as electrophilic fluorinating reagents. The counteranions of these salts, although they are not directly involved in ...
Also used by some bacteria. Dinitrogenases, essential for nitrogen metabolism, normally use molybdenum but in its absence vanadium (or iron) will substitute. [72] Vanadium is also an essential for a variety of peroxidases found in many taxonomic groups, including bromoperoxidases, haloperoxidases, and chloroperoxidases. [73]
Some important organofluorine compounds. A: fluoromethane B: isoflurane C: a CFC D: an HFC E: triflic acid F: Teflon G: PFOS H: fluorouracil I: fluoxetine Organofluorine chemistry describes the chemistry of organofluorine compounds, organic compounds that contain a carbon–fluorine bond.
The chemical element nitrogen is one of the most abundant elements in the universe and can form many compounds. It can take several oxidation states; but the most common oxidation states are -3 and +3. Nitrogen can form nitride and nitrate ions. It also forms a part of nitric acid and nitrate salts.
The gas used is usually inert, or of a nature that protects the integrity of the packaged goods, inhibiting unwanted chemical reactions such as food spoilage or oxidation. Some may also serve as a propellant for aerosol sprays like cans of whipped cream. For packaging food, the use of various gases is approved by regulatory organisations. [1]