Endothermic & Exothermic Reactions

Jules Bruno
Was this helpful?
exo thermic reactions involve releasing thermal energy by the system to the surroundings. Now we're gonna say as molecules in our system release heat, they slow down and with enough energy loss, they form bonds. So exotic reactions are heat releasing bond forming reactions. We're gonna say in terms of face changes, let's think of it as energetic gas molecules as we release heat. Those water molecules they're gonna come closer together. So think of liquid gasses, water bouncing all over the place in a container. They slowly start to release their heat and they slow down because they're losing energy. If they slow down enough, they condense into a liquid. So this is condensation. If the liquid water that we've collected, we put it in the freezer, they will continue to lose heat and they will solidify. So liquid to solid is freezing some substances under right conditions. They can skip the liquid phase altogether. One example is carbon dioxide, we call it dry ice. You could take it out of a very cold container where it's in its gaseous phase and put it outside. It'll skip the liquid phase altogether. So if you're going from a gas to if you're going from a gas to a solid though where we're taking that gaseous um carbon dioxide and putting it back into the container where it solidifies again, that's called deposition. Now let's think about it, let's say container has a liquid and that liquid is an Excel thermic reaction. It's exo thermic so it'll be releasing heat. So if I were to touch that container, I would feel the heat that it's releasing to my hand. So X. Academic reactions feel warm to the touch Now if we don't think of it in terms of an energy diagram in an energy diagram, our Y axis is our energy and then X axis is the progress of the reaction. Remember the whole point of a chemical reactions to go from react inTS two products. And what we need to realize is that in an XR thermic reaction the reactions have more energy. They release their excess energy and they dropped down to become products. Over time the products have less energy because we're releasing energy to go from reacting to product. Our entropy delta H. Would have a negative sign. So just remember this is the way we depict an X. A. Thermic reaction in terms of an energy diagram.