) CH⇤ + H⇤ step 5 CH⇤ + O⇤ * ) CO⇤ + H⇤ reaction enthalpy was smaller than 4E 0 a . The reaction to achieve the fourth step was also written in the reversed direction in the model, as CH⇤+H⇤ * ) CH 2 ⇤+⇤. This reaction was less endothermic on the hypothetical metal than on Pt, so BMA lowered its barrier (green line) based on the expression in range 4E 0 a < H rxn < 4E 0 a . In contrast, the CMPO model did not lower the barrier (in the reverse direction) of the Arrhenius expression, leading to a higher barrier (blue line) for step 4 and slower rate. Additionally, the activation energy in step 5 was estimated in the reverse, endothermic, direction (from adsorbed CO⇤ and H⇤ to CH⇤ and O⇤). LSRs altered it to be more endothermic on the hypothetical metal surface than on platinum. Thus the activation energy is raised by BMA according to the expression at range H rxn > 4E 0 a . The CMPO model (blue line) does not raise the barrier for step 5, despite the reaction becoming more endothermic in the direction written, leading to an unreasonably low submerged barrier, but BMA is able to adjust the barrier to a reasonable level (green line).