Chapter summary
Reaction Kinetics, at a glance
Infer a rate law from evidence and explain how concentration, temperature and catalysts change reaction speed.
A-Level 8873, revised syllabus (2026-2027)
Quick revision
Revisit the essentials, then return to an explanation when you need it.
| Change | Essential explanation |
|---|---|
| Concentration | More particles per volume; collision frequency changes; use the measured order. |
| Temperature | Larger fraction above Ea plus more frequent collisions; k increases. |
| Catalyst | Lower-Ea pathway; distribution unchanged at the same temperature. |
| First-order half-life | Equal times for successive halvings, independent of initial concentration. |
| Enzyme extremes | Active-site shape/interactions change; extremes may denature the protein. |