Catalysts and Potential Energy Diagrams

Mr. Adams from Midwood High School reviews potential energy diagrams, focusing on the comparison of potential energy between reactants and products. He explains the concept of change in enthalpy (Delta H) and how to calculate it. The video covers the characteristics of exothermic and endothermic reactions, including how to identify them on energy diagrams. Mr. Adams also discusses activation energy, the role of catalysts, and provides practical examples to illustrate these concepts.

What do potential energy diagrams primarily compare?

• The speed of a reaction

• The potential energy of reactants and products

• The color change in a reaction

• The mass of reactants and products

How is the change in enthalpy (Delta H) calculated?

• By adding the potential energy of reactants and products

• By dividing the potential energy of products by reactants

• By subtracting the potential energy of reactants from products

• By multiplying the potential energy of reactants and products

What indicates an exothermic reaction on a potential energy diagram?

• Reactants have higher potential energy than products

• The diagram has no activation energy hill

• Products have higher potential energy than reactants

• Delta H is positive

Which mnemonic device helps remember exothermic reactions?

• COOLDOWN

• PUREX

• PARENTS

• HEATUP

What does the activation energy of a reaction represent?

• The energy absorbed by the reactants

• The total energy of the products

• The energy required to start a reaction

• The energy released by the reaction

How can you identify the activation energy of the reverse reaction?

• By subtracting the activation energy from the potential energy of products

• By adding the potential energy of reactants and products

• By subtracting the potential energy of products from reactants

• By subtracting the potential energy of reactants from the activation energy

What is the primary function of a catalyst in a reaction?

• To increase the potential energy of reactants

• To decrease the potential energy of products

• To increase the overall energy of the system

• To lower the activation energy

What does a catalyst NOT affect in a potential energy diagram?

• The potential energy of products

• The activation energy

• The potential energy of reactants

• The speed of the reaction

What happens to the activation energy hill when a catalyst is used?

• It disappears

• It remains unchanged

• It lowers

• It becomes steeper

What is the effect of a catalyst on the speed of a reaction?

• It slows down the reaction

• It speeds up the reaction

• It has no effect

• It reverses the reaction