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Dynamic Chemical Equilibrium

The Challenge

  • Describe chemical equilibria at the molecular level as a dynamic process.
  • Simulation of a Chemical Equilibrium

    The program illustrates what might be going on in a system that is at equilibrium. At the microscopic level (i.e. looking at the molecular species), the state of equilibrium does not mean that there is no change. However, the equilibrium constant K remain essentially constant. The following point will be illustrated.

    In this system, there are four (abstract) chemical species, each represented by a symbol. They may move around in the enclosed system, changing into one another. At any moment, their numbers may be counted, and the 'equilibrium constant' calculated.

    It takes a lot more work to write a simulation involving moving molecules, and here is one that only indicates the changes of molecules. You may observe the equilibrium constant at any time by pressing the key


    during the simulation.

    Record 10 such equilibrium constants, and calculate their average value. You should use the appropriate number of significant figures.

    Compare the value you have obtained with that obtained by the person sitting next to you and see if the average values are the same. How many significant figures do you think there should be for this system?

    After you have read this file, you may press the (Del) key to see one of the pictorial illustration of chemical equilibrium at the microscopic level.

    Confidence Building Questions