Final answer:
A potential energy diagram can provide information about the energy changes and type of reaction occurring in a solution formed between molecules A and B.
Step-by-step explanation:
A potential energy diagram is used to show the energy changes that occur during a chemical reaction. For a solution formed between molecules A and B, the diagram would show the initial energy of the reactants and the transition state, as well as the energy of the products. The diagram can provide information about the reaction's activation energy, enthalpy change, and whether the reaction is exothermic or endothermic. In this case, if the reaction yields a decrease in system enthalpy, it would be considered an exothermic reaction.