- #1

Mangoes

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## Homework Statement

My problem is with a portion of a much larger problem, I'm working on an exercise involving the production of synthesis gas in where there's a reactor in which it is postulated that the following reactions take place:

CH

_{4}+ CO

_{2}⇔ 2CO + 2H

_{2}

CO + H

_{2}O ⇔ CO

_{2}+ H

_{2}

CH

_{4}+ H

_{2}O ⇔ CO + 3H

_{2}

CH

_{4}+ 2H

_{2}O ⇔ CO

_{2}+ 4H

_{2}

One of the problems of the question asks me to write down a reaction matrix to determine the independence of the reactions.

## The Attempt at a Solution

My textbook doesn't cover this, but I was given a handout that covers the method. The handout explains to form a matrix by the stoichiometric coefficients of the species. In the example above, the matrix will be a 4x5 matrix, since there are 4 reactions and 5 total species present.

Then through elementary row operations, I am to diagonalize the matrix to determine the independence of the sets.

I'm having a problem setting up the matrix though. From what I've seen, the convention in my handout is to assign negative values to reactants and positive values to products, but I don't see how to determine the order in which I should enter the species.

To give an example of what I mean, if I were to enter the coefficients for CH

_{4}in the first column, CO in the second column, CO

_{2}in the third column, H

_{2}in the fourth column, and H

_{2}O in the fifth column, the matrix would look like this:

-1 2 -1 2 0

0 -1 1 1 -1

-1 1 0 3 -1

-1 0 1 4 -2

(Apologies for the cluster, I don't know how to write matrices in here)

This can be reduced to yield the independent equations:

CO

_{2}+ 4H

_{2}⇔ CH

_{4}+ 2H

_{2}O

CO

_{2}+ H

_{2}⇔ H

_{2}O + CO

However, if I were to pick a different ordering for my entries, such as CO for my first column, water for my second column, methane for my third column, carbon dioxide for my fourth column, and hydrogen for my fifth column, I can solve that matrix to get these independent equations:

CH

_{4}+ CO

_{2}⇔ 2CO + 2H

_{2}

CO

_{2}+ 4H

_{2}⇔ CH

_{4}+ 2H

_{2}O

One of the equations in the two sets is equal, but what's the deal with the two equations that don't match? Are they independent of one another or can it be shown they are multiples of one another if I make the appropriate operations?

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