Hello Aspirant,

Markovnikov’s rule predicts the outcome of addition reaction carried out on addition of protic acid HX to an asymmetric alkene, also called hydrohalogenation (under standard conditions). It was formulated by Vladimr Markovnikov in 1865 .

When a protic acid HX (X = Cl, Br, I) is added to an asymmetrically substituted alkene, addition of acidic hydrogen takes place at the less substituted carbon atom of the double bond, while halide X is added to the more alkyl substituted carbon atom. In other words, hydrogen is added to the carbon atom with more number of hydrogen atoms attached to it and halide is added to the carbon atom with least number of hydrogen atoms.