Catalyst is a substance that increases the rate of reaction by lowering the Activation Energy (Ea) of a reaction.
Concept #1: Catalyzed vs Uncatalyzed Reactions
Example #1: A certain reaction has an enthalpy value of –20 kJ and an activation energy of 40 kJ. A catalyst is found that lowers the activation energy of the reaction by 10 kJ. What is the total difference in energy between the products and the transition state?
Practice: Which of the following statements is true regarding the energy diagram provided?
i. The reaction is endothermic.
ii. Activation energy would be less than + 10 kJ after a catalyst is added.
iii. The reaction absorbs energy.
iv. Activation energy would be greater than + 10 kJ after a catalyst is added.
a) I only b) II only c) I and III d) II, III and IV
