Energy ChangesKey Facts

Key Facts: Exothermic Reactions

Part of Exothermic Reactions · GCSE GCSE Chemistry revision

This key facts covers Key Facts: Exothermic Reactions within Exothermic Reactions for GCSE Chemistry. Revise Exothermic Reactions in Energy Changes for GCSE Chemistry with 20 exam-style questions and 14 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 7 of 12 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.

Topic position

Section 7 of 12

Practice

20 questions

Recall

14 flashcards

📌 Key Facts: Exothermic Reactions

  • Temperature increases — the reaction mixture and surroundings get warmer
  • Energy is released — transferred from reaction to surroundings
  • ΔH is negative — enthalpy (energy change) is less than zero (e.g., ΔH = -400 kJ/mol)
  • Energy profile dips down — products lower than reactants on diagram
  • Everyday uses: Hand warmers, self-heating cans, heating pads
  • Reversible exothermic — if reversed, the reaction is endothermic

Keep building this topic

Read this section alongside the surrounding pages in Exothermic Reactions. That gives you the full topic sequence instead of a single isolated revision point.

Practice Questions for Exothermic Reactions

In an exothermic reaction, energy is transferred:

  • A. From the surroundings to the reaction mixture
  • B. From the reaction mixture to the surroundings
  • C. Neither absorbed nor released
  • D. Only as light, not heat
1 markfoundation

Explain, in terms of bond breaking and bond making, why combustion is an exothermic reaction.

2 marksstandard

Quick Recall Flashcards

What does "exo" mean?
Outside/exit — energy exits to surroundings
What is an exothermic reaction?
A reaction that releases/transfers energy to the surroundings

20 questions on Exothermic Reactions — practise free

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