Endothermic and exothermic chemical reactions will be addressed in Chapter 6, Lesson 7. What is the catalyst in this activity? A substance in yeast. What evidence do you have that hydrogen peroxide ...

Iron oxide, aluminum, and a catalyst are placed in a flowerpot ... products and smaller energy arrows going into the reactants. In this reaction, the temperature goes down, so it is endothermic. In an ...

Catalysts are useful because they do not get used up during a reaction. Exothermic and endothermic reactions Exothermic reactions release energy into the surroundings, so they usually feel hot.