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.

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter14: Chemical Equilibrium

Section: Chapter Questions

Problem 47P

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