When a chemical reaction is at equilibrium, Q (the reaction quotient) is equal to K (the equilibrium constant). If a stress is applied to the mixture that changes the value of Q, then the system is no longer at equilibrium. To regain equilibrium, the reaction will either proceed forward or in reverse until Q is equal to K once again. Alternatively, equilibrium can be disrupted by a change in temperature, which changes the value of K. The result however is the same, and the reaction will proceed forward or in reverse until Q is equal to the new K. Le Châtelier's principle summarizes this idea: If a stress is applied to a reaction mixture at equilibrium, a net reaction occurs in the direction that relieves the stress.

When a chemical reaction is at equilibrium, Q (the reaction quotient) is equal to K (the equilibrium constant). If a stress is applied to the mixture that changes the value of Q, then the system is no longer at equilibrium. To regain equilibrium, the reaction will either proceed forward or in reverse until Q is equal to K once again. Alternatively, equilibrium can be disrupted by a change in temperature, which changes the value of K. The result however is the same, and the reaction will proceed forward or in reverse until Q is equal to the new K. Le Châtelier's principle summarizes this idea: If a stress is applied to a reaction mixture at equilibrium, a net reaction occurs in the direction that relieves the stress.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter12: Chemical Equilibrium

Section: Chapter Questions

Problem 61QRT

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