Dynamic Equilibrium Definition (Chemistry)

The rates of the forward and reverse reactions are equal at dynamic equilibrium.
The rates of the forward and reverse reactions are equal at dynamic equilibrium. Rafe Swan, Getty Images
By
Anne Marie Helmenstine, Ph.D.
Chemistry Expert
  • Ph.D., Biomedical Sciences, University of Tennessee at Knoxville
  • B.A., Physics and Mathematics, Hastings College
Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels.
our editorial process
Anne Marie Helmenstine, Ph.D.
Updated March 08, 2019

A dynamic equilibrium is a chemical equilibrium between a forward reaction and the reverse reaction where the rate of the reactions are equal. At this point, the ratio between reactants and products remains unchanged over time. For elementary reaction, the equilibrium constant may be expressed in terms of the rate constant.

For the reaction:

A ⇌ B

The equilibrium constant K is:

K = [B]eq / [A]eq

Source

  • Atkins, P.W.; de Paula, J. (2006). Physical Chemistry (8th. ed.). Oxford University Press. ISBN 0-19-870072-5.