AbstractCHARLES W. SOLBRIGThe problem of convective diffusion with a first order reaction on one wall of a catalytic reactor is solved to implement the determination of rate constants from overall conversion measurements. The analysis applies to an isothermal gas mixture with constant physical properties and a parabolic velocity profile. A complete separation of variables, an entrance region, and a fully developed solution as well as asymptotic expressions for large eigenvalues are presented.A formula is given which expresses the Nusselt number as a function of the rate constants. These quantities combine as additive resistances to form an effective rate constant. By analogy, one could apply these results to a plate heat exchanger with a finite wall resistance.