Question

Why the addition reactions are given by only unsaturated hydrocarbons ?

Answer 1

Answer:

Explanation:because they are unsaturated. They have extra bonds between carbon atoms. These bonds can spilt and each of the two electrons from the bond fission can combine with and atom/radical to undergo addition reaction.

Answer 2

Addition reaction is a type of reaction in which two or more molecules combine with each other to form a single substance. ... Substitution reaction does not add any atom to the hydrocarbon because it takes place only in saturated hydrocarbons(containing only single bonds).