According to Markownikoffs rule, the addition of a unsymmetrical reagent (HX) to an unsymmetric alkene takes place in such a way that the negative part of the reagent will be attached to the carbon atom which contains lesser number of H-atom. Hence, it is best applicable to the reaction between C3H6 and HBr . unsymmetricalkeneCH3CH=CH2+HBrCH3−Br∣CH−CH3