Self test 4.4A

[Jineava_To_3N]

Can someone explain part c? I thought the answer was step two but the answer is step one.

[Hao 1I]

Noting that the y-axis is the potential energy, step 1 requires the most potential energy. Therefore it has the highest activation energy. The difference between TS 1 and the initial value has a greater energy barrier compared to the difference between TS 2 and the local energy minimum.

[Chem_Mod]

Activation energy is the energy difference between the starting phase and the peak of the local crest,. The largest activation energy would thus be the largest change in "height" in this graph.

For step two you can see that the energy difference between the intermediate and the second peak is not as large as from the reactants to the first peak