We recently proposed the ammonia heat of adsorption as a reactivity descriptor in solid acid catalysis, using it to predict the activity of zeotype catalysts in the propene–methanol reaction (J. Phys. Chem. Lett. 2014, 5, 1516–1521). Here we extend the approach to a series of alkene reactants, establishing transition state energy scaling relations for ethene and butenes. Using these relations in connection with microkinetic modeling, we predict a change in reaction pathway as a function of acid-site reactivity and alkene size. The results illustrate the potential of the descriptor-based approach to model acid-catalyzed reactions and efficiently screen for improved solid acid catalysts.