Method of quasi-stationary variables

The second assumption (z = 0) of the Bodenstein hypothesis as a consequence of the first (e = 0) is reasonable. Just arguing from a mathematical point of view assumption 1 is neither a necessary nor sufficient condition for the validity of assumption 2, For this reason in the case of the method of quasi-stationary variables one avoids assumption 1 and takes for the changing concentration 

For this reason the following time dependencies for the change in the concentration of the starting material A and the product D result  

As long as the condition for the quasi stationary state is fulfilled, the reaction follows an order of zero. At time 

The example proves the validity of the method of quasi-stationary variables under certain conditions. But this fact does not imply the answer to the question on the relative values of rate constants A , and concentrations 

Oq to o respectively, to be able to describe the progress of the reaction by the approximation correctly. 

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