Chemistry · Hydrocarbons
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Which of the following alkenes is the most reactive towards the addition of bromine?
- A
2-Butene
- B
Ethene
- C
2-Methyl-2-Butene
- D
Propene
The reactivity of alkenes towards electrophilic addition generally decreases as substitution increases. Ethene is the least substituted alkene among the choices, making its double bond more exposed and reactive towards bromine.
This option is incorrect. 2-Butene is a disubstituted alkene, which makes it more stable and less reactive towards bromine compared to less substituted alkenes.
This option is correct. Ethene is a monosubstituted alkene, making it more reactive towards bromine due to less steric hindrance and greater availability of the double bond for addition reactions.
This option is incorrect. 2-Methyl-2-butene is a tetrasubstituted alkene, which is highly stable and therefore less reactive towards bromine compared to less substituted alkenes.
This option is incorrect. Propene is a monosubstituted alkene, but it is still less reactive than ethene due to additional steric hindrance from the methyl group compared to ethene's simpler structure.
Tagged under Chemistry · Hydrocarbons