I am trying to create a model for rate of reaction. What I want it to do is start with 100 cells coloured yellow and then at a specific rate they change independantly blue as goverened by a rate value in another cell. The rate is also dependant though on how many cells are still yellow at the time as it will slow down the fewer there are. As the number of blue cells increases they can change back to being yellow goverened by a rate in another cell. At the end they should then level out an an equilibrium wuth a certain number blue and a certain number yellow as the two rates are the same. I thought this might be possible with a loop function if anyone has any ideas do please let me know. If you also think it is impossible to do please let me know.

Many thanks

Jack