JAMB - Chemistry (2025 - No. 28)
The major product when 2-methylpropene reacts with HCl is
2-chloro, 2-methylpropane
1-chloro,2-methylpropane
3-chloro, 2-methylpropane
2-chloro,3-methylbutane
Explicació
The reaction between 2-methylpropene and HCl is an electrophilic addition reaction that follows Markovnikov's rule. This rule states that in the addition of a hydrogen halide (HX) to an unsymmetrical alkene, the hydrogen atom (H) adds to the carbon atom of the double bond that already has more hydrogen atoms, and the halide atom (Cl) adds to the carbon atom with fewer hydrogen atoms.
CH\(_3\)C(CH\(_3\))=CH\(_2\) + HCl → CH\(_3\)C(CH\(_3\))Cl - CH\(_3\)
2-methylpropene 2 -Chloro, 2-methylpentane
This results in the formation of a more stable tertiary carbocation intermediate, leading to the major product 2-chloro, 2-methylpropane.