Study Notes
Catalysts increase the rate of a chemical reaction by providing an alternative pathway with lower activation energy, allowing more effective collisions between reactant molecules.
- Catalyst — a substance that increases the rate of a chemical reaction without being consumed. Example: Enzymes in biological reactions.
- Homogeneous Catalyst — a catalyst that is in the same phase as the reactants. Example: Acid catalysts in liquid reactions.
- Heterogeneous Catalyst — a catalyst that is in a different phase than the reactants. Example: Solid catalysts in gas reactions.
Exam Tips
Key Definitions to Remember
- Catalyst: A substance that increases the rate of a reaction without being consumed.
- Homogeneous Catalyst: A catalyst in the same phase as the reactants.
- Heterogeneous Catalyst: A catalyst in a different phase than the reactants.
Common Confusions
- Confusing homogeneous and heterogeneous catalysts based on their phases.
- Misunderstanding how catalysts lower activation energy.
Typical Exam Questions
- What is a catalyst? A substance that increases the rate of a reaction without being consumed.
- How does a catalyst affect activation energy? It provides an alternative pathway with lower activation energy.
- What is the difference between homogeneous and heterogeneous catalysts? Homogeneous catalysts are in the same phase as reactants, while heterogeneous catalysts are in a different phase.
What Examiners Usually Test
- Understanding of how catalysts work to lower activation energy.
- Ability to distinguish between homogeneous and heterogeneous catalysts.