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Fluorine is a chemical element; it has symbol F and atomic number 9. It is the lightest halogen [note 1] and exists at standard conditions as pale yellow diatomic gas. Fluorine is extremely reactive as it reacts with all other elements except for the light inert gases. It is highly toxic.
Fluorine, in the form of fluoride, is considered to be a micronutrient for human health, necessary to prevent dental cavities, and to promote healthy bone growth. [28] The tea plant (Camellia sinensis L.) is a known accumulator of fluorine compounds, released upon forming infusions such as the common beverage. The fluorine compounds decompose ...
The halogens (/ ˈ h æ l ə dʒ ə n, ˈ h eɪ-,-l oʊ-,-ˌ dʒ ɛ n / [1] [2] [3]) are a group in the periodic table consisting of six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and the radioactive elements astatine (At) and tennessine (Ts), though some authors [4] would exclude tennessine as its chemistry is unknown and is theoretically expected to ...
It is the principal industrial source of fluorine, often in the form of hydrofluoric acid, and is an important feedstock in the preparation of many important compounds including pharmaceuticals and polymers such as polytetrafluoroethylene (PTFE). HF is also widely used in the petrochemical industry as a component of superacids.
Because the fluorine and chlorine atoms differ greatly in size and effective charge from hydrogen and from each other, the methane-derived CFCs deviate from perfect tetrahedral symmetry. [5] The physical properties of CFCs and HCFCs are tunable by changes in the number and identity of the halogen atoms. In general, they are volatile but less so ...
Fluorine is often added to drug molecules during drug design, as even a single atom can greatly change the chemical properties of the molecule in desirable ways. Because of the considerable stability of the carbon–fluorine bond , many drugs are fluorinated to delay their metabolism , which is the chemical process in which the drugs are turned ...
Fluorine forms compounds with all elements except neon and helium. In particular, it forms binary compounds , named fluorides , with all said elements except argon . All of the elements up to einsteinium , element 99, have been checked except for astatine and francium , [ 24 ] and fluorine is also known to form compounds with mendelevium ...
In order to combat the potential global warming effects of F-gases, and as part of the EU's Kyoto protocol commitments, in 2006 the European Union passed two pieces of legislation controlling their use: the F-gas Regulation (EC) No 842/2006 and the Mobile Air Conditioning Directive Directive 2006/40/EC. The F-gas Regulation adopts an approach ...