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Haloalkanes

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INTRODUCTION
Haloalkanes or also known as alkyl halides or halogenoalkanes are organic compound in which one or more hydrogen atoms of an alkane have been subtitued by halogen atoms (F,Cl, Br, I) We can also assume that haloalkanes as halogen derivative of alkanes. Monohalo derivatives have the general formula, C_n H_(2n+1) X, or RX where R represents the alkyl group and X represents the halogen atom. Members of the haloalkane homologous series have the functional group

C ---- R

They are a subset of the general class of halocarbons. Haloalkanes are widely used commercially and, consequently, are known under many chemical and commercial names. They are used as flame retardants, fire extinguishants, refrigerants, propellants, solvents, and pharmaceuticals. Haloalkanes can be produce from alkanes, alcohols. Alkenes and carboxylic acids. Haloalkanes are reactive towards nucleophiles. They are polar molecules, the carbon to which the halogen is attached is slightly electropositive where the halogen is slightly electronegative. This results in an electron deficient (electrophilic) carbon which, inevitably, attracts nucleophiles. Nucleophiles are Lewis bases where it is electron donor. Nucleophiles are negative ions or molecules that have lone pair of electrons. They are also known and nucleophilic reagents.
There are five types of reactions that can occurs, they are addiction reaction, substitution reaction, elimination reaction, reduction and also oxidation. In this discussion, we will see there will be competition occurs between substitution and elimination during the haloalkanes reaction. Subtitution is the replacement of one atom to another atom or group in a molecule. Rather than creating a molecule with the halogen substituted with something else, one can completely eliminate both the halogen and a nearby hydrogen, thus forming an alkene by dehydrohalogenation

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