Predict the major product formed on adding HCl to isobutylene and write the IUPAC name of the product. Explain the mechanism of the reaction.

The major product will be the 2-Chloro-2-Methyl propane

The reaction mechanism involves the electrophilic addition reaction according to the Markovnikov Rules.

The reaction mechanism is

Isobutylene breaks into the primary and secondary carbocation in the presence of H⁺ ion.

A secondary carbocation is much stable due to the +R effect of methyl group so it is more stable to undergo the electrophilic addition reaction.

Thus, major product is 2-Chloro-2-Methyl propane.