A SIMPLIFIED INTEGRATION TECHNIQUE FOR REACTION-RATE LAWS OF INTEGRAL ORDER IN SEVERAL SUBSTANCES

We have shown here a number of features of rate laws with integral orders in several substances. The rate laws can be integrated quite easily if the process of separation of variables is extended to all the concentration variables. The separation of the concentration variables can be accomplished using only the material-balance condition. The integration formulas obtained for simple reaction kinetics can be used to facilitate the integration of more complicated rate laws. The resulting integrations are simpler than the conventional method of using material balance to express all of the concentration variables in terms of one of the concentration variables. Complicated rate laws can ultimately be decomposed into the same differential expressions as those found in first- or second-order reactions in one variable.