Fluorine electronegativity

C o solubility increases in the similar sequence, from iodobenzene to chlorobenzene. The exception is fluorobenzene in which C6o solubility is lower than in iodobenzene. Apparently, in the case of interaction between fluorobenzene and C6o fullerene the factor of high fluorine electronegativity prevails. Moreover, as Table 3 indicates the fluorobenzene nitration gives rise to mainly para-isomer and very little ort/zo-isomers. Consequently, the entire negative charge is localized in the /jara-position in a fluorobenzene molecule. Therefore, as with Cgo solubility in alkyl derivatives of benzene (Table 2), one can anticipate that for the C6o molecule that is an electrophilic reagent, the ortho-position will be the more preferential location for electrophilic attack than the /w/ra-position. 

An example of an ionic bond is that formed between sodium (electronegativity 0.9) and fluorine (electronegativity 4.0). The difference in electronegativity between these two elements is 3.1. In forming Na F , the single 3t valence electron of sodium is transferred to the partially filled valence shell of fluorine ... 

This ability to bring out high oxidation states is exhibited also by fluorine it is to be attributed to the high electronegativities of oxygen and fluorine.)... 

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... 

Chlorine has a lower electrode potential and electronegativity than fluorine but will displace bromine and iodine from aqueous solutions of bromide and iodide ions respectively ... 

The oxides of fluorine are more correctly called oxygen fluorides because of the greater electronegativity of fluorine. 

Fluorine is the most electronegative and reactive of all elements. It is a pale yellow, corrosive gas, which reacts with most organic and inorganic substances. Finely divided metals, glass, ceramics, carbon, and even water burn in fluorine with a bright flame. 

Carbon-fluorine bonds are quite strong (slightly stronger than C—H bonds) and like polyethylene Teflon is a very stable inert material We are all familiar with the most characteristic property of Teflon its nonstick surface This can be understood by com paring Teflon and polyethylene The high electronegativity of fluorine makes C—P bonds less polarizable than C—H bonds causing the dispersion forces m Teflon to be less than those m polyethylene Thus the surface of Teflon is even less sticky than the already slick surface of polyethylene... 

Fluorine is the most electronegative element and thus can oxidize many other elements to their highest oxidation state. The small size of the fluorine atom facihtates the arrangement of a large number of fluorines around an atom of another element. These properties of high oxidation potential and small size allow the formation of many simple and complex fluorides in which the other elements are at their highest oxidation states. 

Substitution of fluorine for hydrogen in an organic compound has a profound influence on the compound s chemical and physical properties. Several factors that are characteristic of fluorine and that underHe the observed effects are the large electronegativity of fluorine, its small size, the low degree of polarizabiHty of the carbon—fluorine bond and the weak intermolecular forces. These effects are illustrated by the comparisons of properties of fluorocarbons to chlorocarbons and hydrocarbons in Tables 1 and 2. 

Nucleophilic Reactions. The strong electronegativity of fluorine results in the facile reaction of perfluoroepoxides with nucleophiles. These reactions comprise the majority of the reported reactions of this class of compounds. Nucleophilic attack on the epoxide ring takes place at the more highly substituted carbon atom to give ring-opened products. Fluorinated alkoxides are intermediates in these reactions and are in equiUbrium with fluoride ion and a perfluorocarbonyl compound. The process is illustrated by the reaction of methanol and HFPO to form methyl 2,3,3,3-tetrafluoro-2-methoxypropanoate (eq. 4). 

Phenyllithium caimot be formed from fluoroben2ene. Instead, the electronegativity of fluorine makes the ortho hydrogen sufficiently acidic to permit reaction with / -butyUithium in tetrahydrofuran at —50°C to give 2-fluorophenyllithium [348-53-8]. An isomer, 4-fluoropheny11ithium [1493-23-8] was reported to be explosive in the soHd state (167). 

Fluorine is a small atom with a large ego. Fluorine has a high electronegativity so it makes it very reactive, bonding with a great number of atoms. 

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