Final answer:
The chemical reaction between zinc and sulfuric acid to produce zinc sulfate and hydrogen gas is exothermic and cannot typically be reversed just by applying pressure. Reversing such reactions usually requires adding energy and changing conditions that are not related to pressure.
Step-by-step explanation:
The chemical reaction between zinc (Zn) and sulfuric acid (H2SO4) to produce zinc sulfate (ZnSO4) and hydrogen gas (H2) is not one that can typically be reversed simply by applying pressure to the products. This is because the reaction is classified as an exothermic reaction, meaning it releases energy in the form of heat as the reactants transform into products. For the reverse reaction to occur, it would typically require the input of energy to compensate for the loss during the forward reaction, as well as a change in specific conditions that favor the formation of reactants from products which often involves complex chemical procedures.
When discussing the reaction between zinc and sulfur to form zinc sulfide (ZnS), the energetic favorability of this reaction is explained using a reaction coordinate diagram. The initial reaction, where zinc and sulfur are mixed and heated to form zinc sulfide is exothermic, releasing heat. It's not simply a matter of reversing this reaction by applying pressure because the synthesis of ZnS from zinc and sulfur results in a lower energy state for the product compared to the reactants. Therefore, to drive the reverse reaction, energy must be introduced to the system. The reverse reaction would not typically proceed by applying pressure alone.