Properties, such as rate constants or permeabilities, of slightly impure chemical species may vary about some mean value and call for representation by a continuous distribution with a fairly sharp peak. In this sense, they may be regarded as "almost discrete" species and, if represented by Gamma-distributions, are characterized by a single parameter, namely the variance. Almost discrete catalysis, nonmonotonicity of rate constant and a continuous step polymerization are considered. Corrections to the discrete case in terms of powers of the variance can often be obtained.