Which principle are we using in solving Q (iii), (IV) and (vi) ?

 

OH attatched to benzene directly has partial double bond character due to resonance. Hence , OH attatched to CH2 is removed, benzylic position.

Question 4

Markovnokov's addition happens. I is attatched on ortho position, on one side of double bond.

Question 6

Homolysis takes place.Br is added on both sides of double bond.