Chemistry 12 · Chemistry · Lesson 1.5
Reaction mechanisms and catalysis
- Level
- Grade 12
- Reading time
- 11 min reading
- Review
- Last reviewed 2026-09-03
- Standard
- Accuracy standard
- Errata
Abstract
Elementary steps, the rate-determining step and catalysts.
Concept preview
What you will be able to do
- 01Explain the difference between an overall reaction and its mechanism
- 02Identify intermediates and the rate-determining step
- 03Explain how catalysts work and distinguish their types
A balanced equation tells you the overall reactants and products, but it says nothing about how the reaction actually happens. Most reactions do not occur in a single step in which all the reactant molecules collide at once — that would be extraordinarily unlikely. Instead they proceed through a reaction mechanism: a sequence of simple steps that together add up to the overall equation.
School Plan
Reaction mechanisms and catalysis
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