This video lecture from Aliphatic Hydrocarbons (F.Sc. second year Chemistry) covers the Addition reactions of alkenes (Part 2). The reactions of alkenes with halogen acids are discussed. The Markownikov’s rule has been explained in detail that how an unsymmetrical acidic reagent attaches itself to an unsymmetrical alkene. The positive part of halogen acid (the proton) attacks the carbon atom containing double bond with most number of hydrogen atoms followed by the cleavage of pi bond yielding a carbocation which further reacts with negative halogen acid part (the halide) yielding an alkyl halide as final product. Find more e-learning material and educational video lectures in Urdu at maktab.pk. These videos are free to use for promotional and commercial purpose by keeping the credits to Maktab.