Specification Point 3.12:
Know that a catalyst is a substance that increases the rate of a reaction, but is chemically unchanged at the end of the reaction
Catalyst: A substance that increases the rate of a reaction, but is chemically unchanged at the end of the reaction.
- Catalyst will be chemically unchanged so mass will stay the same.
Energy level diagram:
How a catalyst increases the rate of a reaction
Specification Point 3.13:
Know that a catalyst works by providing an alternative pathway with lower activation energy
Catalyst: A substance that increases the rate of a reaction, but is chemically unchanged at the end of the reaction
- The catalyst will provide an alternative pathway requiring lower activation energy so more colliding particles will have the necessary activation energy to react
- This will allow more frequent and successful collisions per second, increasing the rate of reaction
Energy Level Diagrams
*Activation energy without catalyst:
*Activation energy with catalyst:
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Jamie got a First class degree in Chemistry from Oxford University before going on to teach chemistry full time as a professional tutor. He’s put together these handy revision notes to match the Edexcel IGCSE Chemistry specification so you can learn exactly what you need to know for your exams.
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