Conceptually, why is the entropy change of 1 mol of diatomic gas less than 1 mol of an ideal monoatomic gas?
I'm referring to textbook problem 4H.9 btw.
Entropy of Monoatomic vs Diatomic gas
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Re: Entropy of Monoatomic vs Diatomic gas
This is because in 1 mol there are more molecules of a monatomic gas than of a diatomic gas. Therefore the entropy for 1 mol of monoatomic gas is greater.
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Re: Entropy of Monoatomic vs Diatomic gas
I believe the wording of the textbook was a bit confusing for this question.
To put it in more simpler terms, let's say we had 10 atoms.
One container has 10 atoms as single atoms floating around and the other container had 10 atoms into diatomic molecules (5 molecules total; 2 atoms per molecule). Then we can see that the 10 single atoms will create more positional disorder than 5 molecules because there will be more number of possible positions the atoms can occupy, increasing degeneracy and thus entropy.
To put it in more simpler terms, let's say we had 10 atoms.
One container has 10 atoms as single atoms floating around and the other container had 10 atoms into diatomic molecules (5 molecules total; 2 atoms per molecule). Then we can see that the 10 single atoms will create more positional disorder than 5 molecules because there will be more number of possible positions the atoms can occupy, increasing degeneracy and thus entropy.
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Re: Entropy of Monoatomic vs Diatomic gas
Yun Su Choi did a really good job answering your question. If each molecule within a system is what is responsible for the increase in disorder (i.e. increase in entropy), more molecules floating around within a system will cause more disorder.
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Re: Entropy of Monoatomic vs Diatomic gas
Since there are more molecules in one mole of monatomic gas than 1 mole of diatomic, there's more disorder and therefore more entropy :)
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Re: Entropy of Monoatomic vs Diatomic gas
I thought I saw the book say that there is more entropy the more complicated the molecule gets? Did I misread that or is that true?
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