Textbook Problem 7.11 b

[KMcFarland_2L]

How do you sketch the reaction profile for a multi-step reaction? How do you determine the relative heights of the activation energy for each?

[Rohit Srinivas 2D]

For this one you will need to figure out which step is the rate determining one. That is the slowest step. The experimental rate law should clue you in on this. It implies that it has to be a step where H2 is reacting with another molecule. However step 2 has this but has n2o2 instead. This is where the substitution comes into play. You know that the preequilibrium approach works here so the first step has k[no2]^2=k[n2o2]. So you substitute this into the rate law of step 2 for the [n2o2] term and you get that it matches the rate law seen from the experiment. Hope that helps out.

[Nico Medina]

I was wondering this too, thanks for the help!