Links Keywords C3 Chemical Reactions  Define activation energy Describe an experiment to find out if a reaction is exothermic or endothermic C3 Chemical Reactions Links  3.1 Introducing Chemical Reactions  C5.2 Controlling Reactions 3.2 Energetics Draw a labelled reaction profile for an exothermic reaction Describe in terms of bond making and breaking why a reaction is exothermic Draw a flow chart to show how to calculate the energy change in a reaction when given the bond energies Define an exothermic reaction Similarities Differences Draw a labelled reaction profile for an endothermic reaction Define an endothermic reaction Describe in terms of bond making and breaking why a reaction is endothermic Keywords