For an endergonic reaction step, the Hammond postulate allows one to say that . For an endergonic reaction step, the Hammond postulate allows one to say that . the step is rate-determining since it has the smallest Ea the reaction containing this step is overall first order the transition state of the step resembles the products of the step the transition state is precisely symmetric with bond-breaking and bond-forming occurring to the same extent the transition state of the step resembles the reactants of the step