This common misconceptions covers Common Misconceptions within Bond Energies (HT) for GCSE Chemistry. Revise Bond Energies (HT) in Energy Changes for GCSE Chemistry with 20 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 9 of 13 in this topic. Use this common misconceptions to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 9 of 13
Practice
20 questions
Recall
15 flashcards
⚠️ Common Misconceptions
Misconception 1: "Breaking bonds releases energy" (WRONG — this is the most common error!)
This is the single most common mistake in bond energy questions. Breaking bonds ALWAYS REQUIRES energy — it is endothermic. You need to force atoms apart, which costs energy. It is MAKING (forming) new bonds that RELEASES energy. Always: Breaking = Bad (costs energy), Making = Magic (releases energy).
Misconception 2: "If the reaction is exothermic, then the bond-making step must release more energy than the bond-breaking step requires"
This is actually correct! But students often confuse the direction. For exothermic reactions: energy released making bonds > energy needed breaking bonds. ΔH = energy in − energy out = a negative number. The products contain stronger (more stable) bonds than the reactants, so more energy is released forming them than was needed to break the original bonds.
Misconception 3: "ΔH equals the bond energy of one particular bond in the molecule"
ΔH is the TOTAL energy change for the whole reaction, accounting for ALL bonds broken in ALL reactant molecules and ALL bonds formed in ALL product molecules. You must count every bond carefully, remembering to multiply by the stoichiometric coefficients. ΔH is NOT just the energy of one bond.