Fluorine chlorine

Many of the reactions of halogens can be considered as either oxidation or displacement reactions the redox potentials (Table 11.2) give a clear indication of their relative oxidising power in aqueous solution. Fluorine, chlorine and bromine have the ability to displace hydrogen from hydrocarbons, but in addition each halogen is able to displace other elements which are less electronegative than itself. Thus fluorine can displace all the other halogens from both ionic and covalent compounds, for example... 

The mix of inductive and resonance effects varies from one halogen to another but the net result is that fluorine chlorine bromine and iodine are weakly deactivating ortho para directing substituents... 

The most important of the halogenated derivatives of acetic acid is chloroacetic acid. Fluorine, chlorine, bromine, and iodine derivatives are all known, as are mixed halogenated acids. For a discussion of the fluorine derivatives see Fluorine compounds, organic. 

K [14881-07-3], Rb [72151 -96-3], and Cs [72138-72-8]), are prepared by reaction of elemental fluorine, chlorine trifluoride, or xenon difluoride and a mixture of nickel fluoride and alkaH metal fluorides or other metal haHdes (16,17). If the fluorination is carried out using mixed fluorides, a lower temperature can be used, yields are quantitative, and the final products are of high purity. Bis(tetrafluoroammonium) hexafluoronickelate [6310540-8], (NE 2N iF6> prepared from Cs2NiF3 and NE SbE by a metathesis in anhydrous HE, is also known (18). 

Nucleophilic Displacement Reactions. The presence of activating groups, eg, o,p mX.1.0 groups, makes aromatic fluorine reactive in nucleophilic displacement reactions. This has been demonstrated by deterrnination of the relative fluorine—chlorine displacement ratios from the reaction of halonitroben2enes with sodium methoxide in methanol (137) F is displaced 200—300 times more readily than Cl. 

Tungsten disilicide [12039-88-2] WSi2, forms bluish-gray tetragonal crystals (a = 0.3212 nm, c = 0.7880 nm). It is insoluble in water and melts at 2160°C. The compound is attacked by fluorine, chlorine, fused alkaUes, and HNO —HF. It may be used for high temperature thermocouples in combination with MOSi in an oxidising atmosphere. 

Chemical Production. Electrolytic production of chemicals is conducted either by solution (water) electrolysis or fused-salt electrolysis. Fluorine, chlorine, chlorate, and manganese dioxide are Hberated from water solutions magnesium and sodium are generated from molten salt solutions. 

Synthetic procedures are available for the preparation of fluoro, chloro, bromo and iodo compounds from the corresponding lithio derivatives. Perchloryl fluoride (FCIO3), N-chlorosuccinimide, bromine and iodine are examples of reagents which can be used to introduce fluorine, chlorine, bromine and iodine, respectively. 

Hydrogen peroxide, nitric acid, or any other oxidant Fluorine, chlorine, bromine, chromic acid, peroxides... 

I iL-un 12 (CCljFj) which is now banned by the ozone protection treaty. Also used is Dichloro-difluoromethane, Freon 22 (CHClFj), and chloro-difluoromethane. Several analogous compounds containing carbon, fluorine, chlorine, and sometimes hydrogen are available. 

Halocarbon (HCFC) A class of refrigerants that contain fluorine, chlorine, carbon, and hydrogen. 

The Halogens Fluorine, Chlorine, Bromine, Iodine and Astatine... 

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