Stoichiometric table variable-volume

Table 4-1 Stoichiometric Table for Example 4-1 Using the Whole Reactor as a Control Volume and Using Csa as the Composition Variable...

The concentration of one particular species, usually the limiting reactant, is a very convenient variable to use for constant-volume (constant-density) systems. Note that Eqn. (4-7) could have been obtained by substituting the rate equation, Eqn. (4-5), into the design equation for a constant-volume batch reactor, Eqn. (3-8). However, the stoichiometric table still would have been required to relate the various concentrations in the rate equation. 

Notice that the inert gas is included in the stoichiometric table, and that a Total row has also been included. The Total row was not needed to solve constant-volume problems. However, this row is essential for variable-volume (variable-density) problems. 

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