AbstractChemical flow reactors studied include models in which partial mixing and piston flow are present and others which involve partial mixing and short‐circuit. Mixing levels considered extend all the way between the extreme cases of tubular and continuous‐stirred tank reactors. Various orders of reaction are taken into account.The curves presented, obtained through analytical methods, show either the variation of conversion with mixing level at given values of residence time, or relative residence times for a given conversion. Graphical methods of solution are proposed. They involve, in part, a means of computation whereby the overall conversion for a number of reactors in series is obtained from the individual conversions.While isothermal conditions only have been considered, more interesting results are expected when other conditions are applicable, whether isothermal or