Use Hammond’s Postulate to determine which alkene in each pair would be expected to form a carbocation faster in an electrophilic addition reaction:

According to the Hammond postulate, for electrophilic addition reactions of alkene, the transition state is in resemblance with the carbocation formed. Therefore, factors which stabilize the carbocation can also stabilize the transition state.

The most stable carbocation will be form faster compared to relatively less stable carbocations.

The order of the stability of carbocations is given below.

The alkenes when protonated gives the respective carbocations. Since a tertiary carbocation is more stable than a secondary carbocation, it will be formed faster.

The alkenes when protonated gives the respective carbocations. Since a tertiary carbocation is more stable than a secondary carbocation, it will be formed faster.

The alkenes when protonated gives the respective carbocations. Since a tertiary carbocation is more stable than a secondary carbocation, it will be formed faster.