This video lecture from Aliphatic Hydrocarbons (F.Sc. second year Chemistry) covers the Addition reactions of alkenes (Part 1) including Hydrogenation and Halogenation. Hydrogenation or the addition of hydrogen takes place in Pd/Pt catalysts at lower temperatures or with nickel at higher temperatures. Raney nickel formation and usage as a catalyst for hydrogenation is discussed followed by hydrogenation of benzene to cyclohexane and the corresponding enthalpies of hydrogenation. Halogenation of Alkenes is explained as an electrophylic addition followed by the formation of halonium ion which reacts with neuleophilic halogen ion yielding a vicinal dihalide (two halide groups on adjacent carbon atoms). 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.