Draw the complete mechanism for each polar reaction below.

(a)

(b)

(c)

This rule gives an idea of the addition of hydrogen halide to an unsymmetrical alkene. When an unsymmetrical reagent is added to an unsymmetrical alkene then the negative part of the reagent goes to that carbon atom which carries less number of hydrogen atoms means to the more substituted carbon.

(a) In the first reaction alkene $\pi$ bond, the abstract hydrogen atom of hydrogen halide, and in the next step carbocation formed abstract the halide ion.

Reaction A

(b) In the first reaction alkene $\pi$ bond, the abstract hydrogen atom of hydrogen halide, and in the next step carbocation formed abstract the halide ion.

c) In the first reaction alkene$\pi$bond abstract hydrogen atom of hydrogen halide and in the next step carbocation formed abstract the halide ion.

reaction c