Question

Which of the following best describes the relationship between products and reactants in an endothermic reaction?

The products are water and an ionic salt, and the reactants are H+ ions and OH− ions.
The reactants are simple compounds, and the product is a more complex compound.
The potential energy of the products is greater than the potential energy of the reactants.
The temperature of the products is greater than the temperature of the reactants.

Answer 1

@paki @Nnesha @dan815

Answer 2

Which one do you think it is?

Answer 3

In ALL endothermic reactions, energy is absorbed by the starting materials as they react to form the products. In this case, we must essentially 'force' or put energy in in order to allow them to react together appropriately to drive the reaction towards completion. Thus, the reactants will be of a lower energy, or more thermodynamically stable, than the products. This energy input often comes in the form of heat. This heat is 'absorbed' by the reactants themselves in order to allow them to combine together in the correct manner for the reaction to proceed in the way we want it to.

The opposite case is true for an exothermic reaction, where the products will be thermodynamically more stable (i.e. have a lower energy) than the reactants from which they derived. In this case the excess energy from their formation is offloaded usually as heat given out as the reaction goes to completion. In this case, the reactants are already relatively unstable enough for it to be favorable for them to react to form molecules/species which are more energetically stable (i.e. the products).

We can represent this easier using a Reaction Coordinate Diagram, tracking the energy of the reactants and products as the reaction proceeds:



Hope this information helped you out with the answer to the question @jammy987 !