Reaction is exergonic, cuz energy is being released out
Comparing Stabilities of Alkenes
Evaluate heat given off when C=C is converted to C-C
More stable alkene gives off less heat
Trans
butene generates 5 kJ less heat than cis-butene
Electrophilic Addition forpreparations
The reaction is successful with HCl and with HI as well asHBr
Note that HI is generated from KI and phosphoric acid
Addition of hydrogen bromide to 2-Methyl-propene
H-Br transfers proton toC=C
Forms carbocation intermediate
More stable cation forms
Bromide adds to carbocation
7.4 Addition of Water to Alkenes:Oxymercuration
Hydration of an alkene is the addition of H-OH to to givean alcohol
Acid catalysts are used in high temperature industrialprocesses: ethylene is
converted to ethanol