Which of the following can undergo both addition reactions and substitution reactions?
Answer Details
Benzene is the only compound that can undergo both addition reactions and substitution reactions. This is because of its unique structure, which consists of a ring of six carbon atoms with alternating double bonds. The double bonds in benzene are considered to be "delocalized," meaning that the electrons involved in the bonds are spread out over the entire ring rather than being localized between specific carbon atoms. This delocalization makes benzene relatively stable and resistant to addition reactions, but it also makes it susceptible to substitution reactions. In a substitution reaction, one or more of the hydrogen atoms in the benzene ring can be replaced with another atom or group of atoms. In an addition reaction, on the other hand, two molecules combine to form a single molecule, usually with the addition of a double or triple bond. Because benzene already has a stable ring structure with delocalized double bonds, it is not easily able to undergo addition reactions, but it can undergo substitution reactions.