• write a mechanism and, based on that,
• follow the course of concentrations or rates of change in concentration of reactants, catalysts, intermediates, and products over time.

• [X], ln[X], 1/[X], or d[X]/dt vs. time, and
• d[X]/dt vs. time, [X], or [X]²

Questions to consider include:

1. How do the individual concentrations change over the course of the reaction? Which ones rise and which ones fall? Which ones start small, rise, then fall again?
2. Are the individual changes in concentration (d[X]/dt) related? How so? Are these exact, or only approximate correlations? Why would that be?
3. Is there a rate "constant" for the reaction? If so, how would you get its value?

You can either select from a predefined mechanism or write your own. At a minimum, indicate "<==>" for reversible steps and "--->" for irreversible steps. Clicking on 'check' will fill in the rest of the needed values, at least with default values. Blanks ARE important and represent the end of a formula. So if you mean "Fe+2 + V+2" don't write "Fe+2+V+2". The program isn't THAT smart! Note that rate constants (k_n and k_-n) should be between 0 and 1 here, as 'dt' is 1 second for this simulation, and larger numbers will result in too fast of a reaction. To indicate that a concentration should remain constant, add "(constant)" immediately after its value.