The enrichment factor (epsilon(u)) in the separation unit of ion-exchange and chemical reactions is a function of the enrichment factor of the chemical reaction (epsilon(r,s)) and the "equilibrium coefficients" (zeta) which are determined only by the distribution of the ions in both the solution and ion-exchange phases. The factor can be simply expressed as epsilon(u) = zeta epsilon(r,s). The height of the separation unit is the sum of heights due to ion exchange, chemical reaction, and flow pattern. The height is also due to the "kinetics coefficient" (zeta), which is a function of the distribution as well as the "equilibrium coefficient." The separation efficiency is proportional to zeta/root upsilon, both of which depend on the concentration of ions in the unit. Several schemes for the separation units are also discussed.