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This study compares global rate expressions for CO oxidation over Pt/Al2O3 catalysts from the literature to a recent rate law based on a novel experimental approach. Our new method infers local values of reaction rates from measured concentration profiles along an enlarged isothermal catalytic passage at typical automotive exhaust conditions. Experimental uncertainties are relatively small, so parameters in the rate law can be assigned within close tolerances. Rate laws based on dual-site Langmuir Hinshelwood (LH) mechanisms correlate several of the available databases, including the new one. And activation energies for the CO-O2 reaction in several global rate laws agree with values reported in the surface science literature. However, assigned energies in the CO adsorption equilibrium constant are 25 to 35 kcal/mole lower than they should be.