The interactions of chemical species with a solid surface play a role in many everyday applications such as heterogeneous catalysis, corrosion, and degradation reactions. Understanding the reaction kinetics and thermodynamics via rate constants and equilibrium constants, which require knowledge of the adsorbed species’ entropy, is essential for tuning these surface reaction mechanisms. To reach this goal, we developed a hindered translator and hindered rotor model for calculating the surface entropy and implemented it into two existing python packages for atomic simulation and reaction modeling analysis. We use density functional theory, a computational modeling technique for determining electronic structures at the atomic scale, to calculate surface entropies as well as surface reaction energies. One such reaction we consider is the dissociation of CO into atomic C and O, as a precursor to corrosion reactions in metals. The process of CO breakdown on twelve nickel-based alloy surfaces to make corrosive O and C adsorbates is explored to understand the effect of the alloying atom on the CO reaction energetics. Another surface reaction we consider is the electro-reductive degradation of an electrolyte solvent on the anode surface in lithium-ion batteries. The dissociation of fluoroethylene carbonate on two lithium silicide surfaces is explored to understand the mechanisms and energetics of the degradation reaction and to understand the role of different battery charge states on the reaction. Altogether, these studies serve to advance the field of surface science.