Stoichiometry and the Reaction Matrix
The mass action statements (i.e., what we commonly refer to as reactions) that represent the conversion of reactants to products can be represented as algebraic statements.
where 
is
the stoichiometry matrix and A is the species matrix. The minimum number of reactions that
is needed to describe changes in concentration is found by determining the rank of .
THE PROBLEM STATEMENT
The following set of possible chemical reactions have been suggested to describe the reactions that occur during the decomposition of nitric anhydride,
THE QUESTIONS
1. Write the stoichiometric matrix for the species matrix A
Run the simulation to determine if you have the specified the matrix correctly. This stoichiometric matrix has a rank of 4, meaning only four linearly independent reactions are needed to describe the rates of production in the material and energy balances.
2. The program asks for you to select different combinations of four reactions (there are nine such combinations) to determine the number of sets of linearly independent reactions (there are five linearly independent sets of four reactions). By inspection you should be able to identify two linearly dependent reactions that, when included in the four reaction sets, will lead to a rank less than 4. What are the two reactions? What does it mean when you select four reactions that lead to a new stoichiometric matrix with a rank less than 4?
Stoichiometry Simulation
Please select a reaction for each row of the matrix.