4.14      represent exothermic and endothermic reactions on a simple energy level diagram

Energy level diagrams show the energy of reactants relative to products. The height difference between them is ∆H for the reaction.

If you draw these for a particular reaction, label an arrow for ∆H with its sign and value on the dotted line, and put in the formulae of the reactants and products on the appropriate horizontal lines.

endothermic energy level diagram

exothermic energy level diagram