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Reversible Reactions Simulation (6 Favorites)

ACTIVITY in Activation Energy, Equilibrium Constants. Last updated April 26, 2019.


In this activity, students will investigate how temperature, activation energy, initial amounts of products and reactants, and type of reaction (exo- or endothermic) effect the equilibrium position of a reaction using a simulation.

Grade Level

High school

AP Chemistry Curriculum Framework

  • Big Idea 6: Any bond or intermolecular attraction that can be formed can be broken. These two processes are in a dynamic competition, sensitive to initial conditions and external perturbations.
  • 6.8 The student is able to use Le Chatelier’s principle to predict the direction of the shift resulting from various possible stresses on a system at chemical equilibrium.


By the end of this lesson, students should be able to

  • See how temperature affects the value of equilibrium constants for endothermic and exothermic reactions.
  • See how activation energy affects.

Chemistry Topics

This lesson supports students’ understanding of

  • Thermodynamics
  • Equilibrium
  • Equilibrium constant
  • Activation energy


Teacher Preparation: 10 minutes

Lesson: one class period


For each group:

  • Computer with access to the internet


No safety precautions need to be observed during this activity.

Teacher Notes

For the Student


Complete the following table using the simulator.
Determine whether you want to test an exo- or endothermic reaction. Change the E a and T, one variable at a time, keeping the other variables constant.



Initial T

Final T

Type of reaction (endo/exo)


Initial A

Initial B

Final A

Final B

K (equilibrium constant)

  1. How does changing Ea affect the reaction? Explain.
  2. How do changes in T affect the value of K?
  3. Is the reaction A → B endothermic or exothermic? Explain.
  4. How do you know when equilibrium is established?
  5. Describe the conditions of a reversible reaction you conduct using the simulator. How do you know it is reversible?