How is the overall energy change of a reaction worked out from bond energies?
Energy released forming bonds subtract energy needed to break bonds
Energy needed to break bonds added to energy released forming bonds
Energy needed to break bonds subtract energy released forming bonds
Energy released forming bonds divided by energy needed to break bonds
39 exam-style questions on AQA GCSE Chemistry 5.1 Exothermic and endothermic reactions, covering 5.1.1 Energy transfer during exothermic and endothermic reactions, 5.1.2 Reaction profiles, and 5.1.3 The energy change of reactions. Each one has a worked solution and a mark scheme showing where the marks go.