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Saladsamurai
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I am reading through a combustion physics text by Law and I am a little confused by this notation for a reaction. He says:
My questions:
1) In this sense, is the "concentration" vi the same as the relative composition? That is, is it simply the "mole fraction?"
2) Both of the summands in the reactants and products run from i = 1 to N. I do not understand this. It seems that this would not allow for the formation of different molecules in the products. That is, it assumes that the reactants and the products are identical. But in the case of a simple reaction like [itex]CO + \frac{1}{2}O_2 \leftrightharpoons CO_2[/itex] it is clear that there are 1) a different number of products than reactants and 2) the subscript "1" in the reactants is not representative of the same molecule as "1" in the products.Is it possible that this reaction is being written "atom wise" (I have never heard of this) instead of as molecules? Or is it that the indices on the left hand side and those on the right hand side are completely independent? That is, the set of "N" molecules in the reactants is a completely different set than the "N" molecules in the products?
Chung K. Law said:Consider a chemical reaction given by
[tex]
\sum_{i=1}^N\nu_i'M_i\leftrightharpoons\sum_{i=1}^N\nu_i''M_i
[/tex]
where Mi is the chemical symbol for the ith species and [itex]\nu_i[/itex] the corresponding molar concentration coefficient ...
My questions:
1) In this sense, is the "concentration" vi the same as the relative composition? That is, is it simply the "mole fraction?"
2) Both of the summands in the reactants and products run from i = 1 to N. I do not understand this. It seems that this would not allow for the formation of different molecules in the products. That is, it assumes that the reactants and the products are identical. But in the case of a simple reaction like [itex]CO + \frac{1}{2}O_2 \leftrightharpoons CO_2[/itex] it is clear that there are 1) a different number of products than reactants and 2) the subscript "1" in the reactants is not representative of the same molecule as "1" in the products.Is it possible that this reaction is being written "atom wise" (I have never heard of this) instead of as molecules? Or is it that the indices on the left hand side and those on the right hand side are completely independent? That is, the set of "N" molecules in the reactants is a completely different set than the "N" molecules in the products?
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