Answer:
Explanation:
This is an example of a Friedel-Crafts alkylation.
Since no organic halide is provided, we'll use an example of how benzene reacts with chloroethane, for instance.
Benzene is not reactive, therefore, we require a catalyst for such a reaction, typically either aluminum chloride or iron(III) chloride. It provides a pathway to add an alkyl chain to the benzene ring by removing the halogen present in the R-Cl molecule.
The mechanism is summarized by:
This is a so-called electrophilic substitution mechanism. To illustrate it with my example, I'm providing an image below.