Energy ChangesTopic Summary
Topic Summary: Reaction Profiles
Part of Reaction Profiles — GCSE Chemistry
This topic summary covers Topic Summary: Reaction Profiles within Reaction Profiles for GCSE Chemistry. Revise Reaction Profiles in Energy Changes for GCSE Chemistry with 28 exam-style questions and 15 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 13 of 13 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 13 of 13
Practice
28 questions
Recall
15 flashcards
Topic Summary: Reaction Profiles
Key Terms
- Reaction profile — energy diagram of a reaction
- Activation energy (Ea) — reactants to peak
- ΔH — reactants to products (overall)
- Transition state — the peak of the profile
- Catalyst — lowers Ea, unchanged at end
Must-Know Facts
- Exothermic: products LOWER than reactants
- Endothermic: products HIGHER than reactants
- Ea = from reactants UP to the peak
- Catalyst: lower peak, same ΔH, same start/end
- Axes: y = Energy, x = Progress of reaction
- Ea is always required — even for exothermic reactions