Which statement is incorrect about activation energy?

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Multiple Choice

Which statement is incorrect about activation energy?

Activation energy is the energy barrier that must be overcome to reach the transition state from the reactants. For a simple elementary step, this barrier is a positive quantity or zero if the reaction is barrierless; in other words, Ea equals the energy of the transition state minus the energy of the reactants and cannot be negative. The claim that activation energies of simple reactions can be negative would imply the transition state lies below the reactants, removing the barrier, which does not fit the definition for a straightforward reaction step. In practice, the rate constant depends on Ea through the Arrhenius factor exp(-Ea/RT), so a positive Ea makes the rate increase with temperature, while Ea = 0 would give a temperature-insensitive rate.

Activation energy is the energy barrier that must be overcome to reach the transition state from the reactants. For a simple elementary step, this barrier is a positive quantity or zero if the reaction is barrierless; in other words, Ea equals the energy of the transition state minus the energy of the reactants and cannot be negative. The claim that activation energies of simple reactions can be negative would imply the transition state lies below the reactants, removing the barrier, which does not fit the definition for a straightforward reaction step. In practice, the rate constant depends on Ea through the Arrhenius factor exp(-Ea/RT), so a positive Ea makes the rate increase with temperature, while Ea = 0 would give a temperature-insensitive rate.

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