The electrophilic addition reaction between propene C3H6 and hydrogen bromide HBr will form 2-bromopropane C3H7Br as the major product. The reaction proceeds as follows:C3H6 + HBr C3H7Br 2-bromopropane In this reaction, the double bond in propene acts as a nucleophile and attacks the electrophilic hydrogen atom in HBr. This leads to the formation of a carbocation intermediate, which is more stable at the secondary carbon due to hyperconjugation. The bromide ion Br- then attacks the carbocation, resulting in the formation of 2-bromopropane.