1. Module 7

1.25. Page 5

Lesson 5

Module 7—Principles of Chemical Equilibrium

Lesson Summary

 

In Lesson 5 you considered the following questions:

  • What is the equilibrium constant?
  • What information about an equilibrium is provided in an equilibrium constant?
In this lesson you learned about the equilibrium constant and the equilibrium law. The equilibrium law is an expression that relates the concentrations of the products to the reactants in a chemical system. The equilibrium law is used to calculate an equilibrium constant. The equilibrium law can be stated as

, where the balanced chemical equation for the system takes the form aA + bB cC +dD

As you found in this lesson, the equilibrium constant is a specific value for a reaction system that is constant for a full range of concentrations. The magnitude of the value for the equilibrium constant provides information about the relative proportions of the products and reactants in the system:

  • if K = 1, then [products] = [reactants]

  • if K > 1, then [products] > [reactants]

  • if K < 1, then [products] < [reactants]