AbstractAn activated diffusion, or site‐hopping, mechanism is used to describe surface diffusion of gases through porous media. This analysis provides a useful and accurate method for correlating data at submonolayer coverages on energetically heterogeneous surfaces. The data needed to use this correlation are surface area and pore structure of the adsorbent, adsorption isotherms at two or more temperatures, and the activation energy for migration. The former quantities are easily determined from Knudsen diffusion and adsorption measurements, while the activation energy can be found from a single permeability measurement. Predictions made in this way show excellent agreement with experimental dat