Figure 4. Breakthrough outlet concentration of Br^- as a function of number of residence time. C₀ is the initial injecting concentration of the tracer Br^- while C is the tracer concentration at the outlet.

This breakthrough curve shows 0 C/CO from 0 residence time until about .75 residence time. The C/CO increases rapidly from 0 to 1 between .75 residence time and 1.33 residence time. C/CO remains steady from 1.33 residence time until 3 residence time where the graph ends. You can see an breakdown of the numbers in the table below.