Catalysts

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Catalysts

1. What is a Catalyst?

• A catalyst is a substance that changes the rate of a chemical reaction without being consumed in the process.
• It lowers the activation energy $(Ea)$, making it easier for reactants to form products.

2. Types of Catalysts

Type	Effect on Reaction
Positive Catalyst	Increases the reaction rate.
Negative Catalyst (Inhibitor)	Decreases the reaction rate.

🔹 Note: The term "catalyst" usually refers to a positive catalyst.

3. How Do Catalysts Work?

✅ Provide an alternative reaction pathway with lower energy requirements.

✅ Reduce the activation energy needed to form the activated complex.

✅ Speed up reactions without being permanently changed or used up.

4. Key Takeaways

✅ Catalysts speed up or slow down reactions without being used up.

✅ Positive catalysts lower activation energy, increasing the reaction rate.

✅ Inhibitors slow down reactions by increasing the activation energy.