This memory aid covers Memory Aids within Bond Energies (HT) for GCSE Chemistry. Revise Bond Energies (HT) in Energy Changes for GCSE Chemistry with 25 exam-style questions and 15 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 11 of 15 in this topic. Use it for quick recall, then test yourself straight afterwards so the memory aid becomes usable in an answer.
🧠 Memory Aids
Breaking = Bad (needs energy), Making = Magic (releases energy)
This is the most important thing to remember for bond energy questions. Break = ENDO (energy in). Make = EXO (energy out).
The formula: "IN minus OUT" = ΔH
ΔH = energy IN (breaking) − energy OUT (making)
If ΔH is negative → more OUT than IN → exothermic (more energy released than absorbed)
If ΔH is positive → more IN than OUT → endothermic (more energy absorbed than released)
Double check rule: "Negative ΔH = nice and warm (exothermic). Positive ΔH = pulls energy from surroundings (endothermic)."
Practice questions for Bond Energies (HT)
Which statement correctly describes the energy change when chemical bonds are broken?
Explain how you would determine, from a bond energy calculation, whether a reaction is exothermic or endothermic.