Chapter summary
Rate of Reactions, at a glance
Explain why reactions speed up, and read what a progress graph actually proves.
O-Level 5086 / 5088 (2026) / SEC G3 K326 / K328 (2027)
Quick revision
Revisit the essentials, then return to an explanation when you need it.
| Term | Definition to write |
|---|---|
| Rate of reaction | The change in the amount (or concentration) of a reactant or product per unit time. |
| Effective collision | A collision between reacting particles that have energy equal to or greater than the activation energy, so that they react. |
Rate describes change per unit time. Concentration, pressure, temperature and exposed surface area affect successful collisions. On a progress graph, slope indicates rate and the final level indicates measured amount.
Quick recall
Why does increasing the concentration of an acid increase the rate of its reaction with magnesium?