Self Test 4.4A part c

[Angela_Pu_3C]

In this it says that given the graph, step one would have the larger Ea, but how can you tell that? I kinda assumed that since the standard gibbs free energy of activation was larger in the second step, it would have the larger Ea. Thanks :)

[garrett_perozich]

When you look at the activation energies, you are looking at the energy needed to move from its previous "state" to the new transition state (TS). So, for Ea1, it is from the reactants "axis", to the top of TS1. For Ea2, though, we have to look at the difference between the intermediate "axis" and the top of TS2. Go back to page 154 in the text and see a visual representation of what I'm saying there. Hope this helps!