Electrophilic addition in alkenes

Alkenes are more reactive than alkanes.
This is due to the C=C double bond.
Mean bond enthalpy is +347 kj mol
The double bond is an area of high electrin density so electrophiles such as Br2 and Hbr are attracted to it.
In alkenes, the bond breaks and a small molecule is added across the two carbon atoms.
Halogenation is an addition reaction in which a halogen is added across the C=C bond.
Adding bromine water to an alkene will form a haloalkene and the bromine water will decolourise.
The test for identifying an alkene is ;
CH2CH2 =Br2 -> BrCH2Br
Haloalkanes can be formed by an addition reaction between a hydrogen halide such as HBr and an alkene.
Hydrogen halides like HCL, HBr and Hl are gases at room temperature so they are bubbled trough the alkene to cause a reaction.
CH2CH2 + HBr -> CH3CH2Br
Hydration is an addition reaction between an alkene and steam
The alkene must be in gaseous form for the reaction to occur.
The temperature must be high, around 300 degree celcius, as must be the pressure about 65 atm.
Phosphoric acid acts as the catalyst
CH2CH2 + H20 -> CH3CH3OH
Alkenes react with concentrated sulfruic acid under cold conditions to…

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