Predict the major product formed when HCl is added to isobutylene, Explain the mechanism involved.

Explanation

`underset("Isobutylene")(CH_(3)-underset(CH_(3))underset(|)C=CH_(2))+HCl to underset("2-Chloro-2-methylpropane")(CH_(3)-underset(CH_(3))underset(|)overset(Cl)overset(|)C-CH_(3))`
The mechanism involved in this reaction is :
Step I
`underset("Isobutylene")(CH_(3)-underset(CH_(3))underset(|)C=CH_(2)) overset(H^(+))to underset(underset("(more stable)")(3^(@) "carbocation"))(CH_(3)-underset(CH_(3))underset(|)overset(+)C-CH_(3))+underset(underset("(less stable)")(1^(@) "carbocation"))(CH_(3)-underset(CH_(3))underset(|)CH-overset(+)CH_(2))`
`3^(@)` carbocation is more stable than `1^(@)` and is predominantly formed.
Step II `CH_(3)-underset(CH_(3))underset(|)overset(+)C-CH_(3) overset(Cl^(-))to CH_(3)-underset(CH_(3))underset(|)overset(Cl)overset(|)C-CH_(3)`