Muhammed, What type of calculation are yu trying to do? Are you trying to create a diagram from data or use a diagram you already have? What reaction are you studying? Is ot CO+1/2O2 => CO2? Or maybe CO+CO C + CO2
Sir Rick Manner The reactions mentioned in the figure that you shared above in the link, I have the reaction constant values, How to calculate the PCO/(PCO+PCO2) ?
If you have a rate constant for CO + 1/2 O2 =>CO2 and for CO+COC + CO2 you can set up a spreadsheet with 100 or even 1000 rows. On row 1 put your initial conditions. Plug the initial Partial pressures into you rate expression(s) to find a reaction rate.. Make a small step in the forward direction for both reactions (calculate delta CO O2, C and CO2 for each step from the kinetics). Repeat the calculation with the new composition for each of the rows of the spreadsheet to fill up all of the cells. When you are done cut the step size in half to see if the answer changes. If it doesn't you are done you have created all of the data you need for a concentration vs time graph. If it has changed keep changing the step size until the concentration vs time doesn't change.
There are fancier programs that will do this for you but I don't know what you have access to and excel should give you the same answer it will give you a better hands on feel for how the reaction actually proceeds. I hope this helps, If you have trouble setting things up send me a message with more details about your kinetic expressions. Initial conditions and rate constants.