A theoretical representation of adsorption by particles injected into a gas stream that was developed previously is used to assess results from a dry sorption injection experiment. The particle-size distribution is required in the theoretical model, and this distribution is measured for the experimental particles. The pore-size distribution is also measured and used to determine particle properties, including the effective diffusivity in the pore passages within the particles, which is required by the model, Comparison of the model and experiment establishes the crucial importance of accurate knowledge of the equilibrium relation for the actual adsorbate-adsorbent system considered and of a reliable representation of particle size and shape.