1. Module 7

1.7. Lesson 2

Lesson 2

Module 7—Principles of Chemical Equilibrium

Lesson 2—Dynamic Equilibrium

 

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In Lesson 1 you observed the colour changes of methylene blue that resulted when the system the indicator was in was shaken or allowed to sit undisturbed. In your analysis of that system you learned that chemical reactions are reversible.

 

To some extent all chemical systems demonstrate reversibility. Therefore, studying the equilibrium of chemical systems involves recognizing the forward and reverse reactions for a system and their reaction rates. For example, if the evaporation of water into the atmosphere is considered the forward reaction for the water in the biosphere system, then precipitation as rain, snow, or fog would be the products of the reverse reaction.

 

You may recall that you learned about reaction rate in Unit A when you learned about the collision-activation theory, which explains the events involved in a chemical reaction. How might the probability of collisions between particles and energy of activation influence a chemical system at equilibrium?

 

In this lesson you will look for evidence of the forward and reverse reactions that occur within chemical systems. By accumulating and interpreting this evidence, you will gain a better understanding of dynamic equilibrium.

 

Consider the following questions as you complete Lesson 2:

  • What is a reverse reaction and why is it important in an equilibrium system?
  • What changes occur during dynamic equilibrium?
Module 7: Lesson 2 Assignment

 

Your lesson assignment consists of a lab. Download a copy of the Module 7: Lesson 2 Assignment to your computer now. You will receive further instructions on how to complete this assignment later in the lesson. You will also receive further information on how to add to the table you began in Lesson 1.

 

You must decide what to do with the questions that are not marked by the teacher.

 

Remember that these questions provide you with the practice and feedback that you need to successfully complete this course. You should respond to all the questions and place those answers in your course folder.