Nitric oxide, $\text{NO}$, and bromine vapour react with each other according to the equation below. $2\text{NO(g)} + \text{Br}_2\text{(g)} \rightarrow 2\text{NOBr(g)} \qquad \Delta H^\circ = -23\ \text{kJ mol}^{-1}$ For this reaction, the activation energy is $+5.4\ \text{kJ mol}^{-1}$. Which reaction pathway diagram is correct for this reaction?
Chemistry 9701 · AS & A Level · Chemical energetics