This introduction covers The Chemistry of Warmth 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 1 of 12 in this topic. Use this introduction to connect the idea to the wider topic before moving on to questions and flashcards.

📖 The Chemistry of Warmth

On a freezing winter's day, you snap a hand warmer and feel it heat up in your pocket. That warmth isn't coming from nowhere — it's being released by a chemical reaction happening inside. Iron powder is reacting with oxygen in the air, and the energy stored in the bonds of the reactants is greater than the energy in the products. The difference? It escapes as heat into your cold hands. This is an exothermic reaction — from combustion keeping you warm at home, to the respiration happening in every cell of your body right now.

🔥 The Hand Warmer Analogy

Exothermic reactions are like hand warmers — they release heat! Think "exit" — energy EXITS the reaction and enters the surroundings. That's why your hands feel warmer, the test tube gets hot, or combustion keeps you cosy. The products have LESS energy than the reactants — the difference escapes as heat!

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

The Chemistry of Warmth

📖 The Chemistry of Warmth

Practice questions for Exothermic Reactions

Quick recall flashcards

20 questions on Exothermic Reactions — practise free