Rates of ReactionHow It Works
How Each Factor Links to Collision Theory
Part of Factors Affecting Rate — GCSE Chemistry
This how it works covers How Each Factor Links to Collision Theory within Factors Affecting Rate for GCSE Chemistry. Revise Factors Affecting Rate in Rates of Reaction for GCSE Chemistry with 20 exam-style questions and 18 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 5 of 13 in this topic. Use this how it works to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 5 of 13
Practice
20 questions
Recall
18 flashcards
⚙️ How Each Factor Links to Collision Theory
Every factor that affects rate must be explained using collision theory. Here is the precise mechanism for each one:
- Temperature: Higher temperature → particles have more kinetic energy → move faster → collide more frequently AND a greater proportion of particles now have energy ≥ Ea → more successful collisions per second → faster rate.
- Concentration (or pressure for gases): More particles in the same volume → particles are closer together → collisions are more frequent → more successful collisions per second → faster rate. (Energy of particles does not change.)
- Surface area: Breaking a solid into smaller pieces exposes more particles at the surface → more particles are available to collide with the other reactant → more collisions and more successful collisions per second → faster rate. (Energy and concentration don't change.)
- Catalyst: Provides an alternative reaction pathway with a lower activation energy → a greater proportion of the existing collisions now have energy ≥ the new, lower Ea → more successful collisions per second → faster rate. Crucially, a catalyst is not consumed — it can catalyse the reaction again and again.