Final answer:
True, a small amount of p-dibromobenzene can indeed be formed as a by-product during the bromination of benzene, especially under certain conditions that favor further substitution.
Step-by-step explanation:
The question refers to the bromination of benzene and the potential formation of by-products, specifically p-dibromobenzene. In typical bromination reactions of benzene, the primary product is mono-substituted bromobenzene due to benzene's high resistance to further substitution; however, the formation of small amounts of poly-substituted products like p-dibromobenzene can occur under certain conditions. This is more likely when excess brominating agent is present and the reaction conditions are such that it can overcome the activation energy for further substitution.
During halogenation reactions, control over reaction conditions is crucial. For example, when benzene is brominated using a catalyst like iron (III) bromide (FeBr3), the reaction is initiated by the formation of the electrophile Br+, which attacks the benzene ring to form bromobenzene. Excess bromine can potentially lead to further substitution to form products such as p-dibromobenzene.
In the provided context, it's indicated that there were special conditions in the experiments to achieve specific bromination on other compounds rather than benzene itself, but without explicit data on the bromination of benzene specifically, one can infer that p-dibromobenzene could be a minor by-product in a bromination reaction.