halogenation#!#reaction

Which of the follwing is not the characteristic of the mechanism of free radical halogenation chain reactions?

|| Bromination || halogenation || nitration || Reimer teimann reaction || Reimer teimann carboxylation || kolbe - schmidt reaction || Reaction OF salicyclic acid (aspirin oil wintergreen,salol) ||

In the presence of a small amount of phosphorous, aliphatic carboxylic acids react with chlorine or bromine to yield a compound in which alpha - hydrogen has been replaced by halogen. This reaction is known as :

Which of the following is halogen exchange reaction ?