Quiz one answer

Boltzmann Equation for Entropy:

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Blake_Katsev_2E
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Quiz one answer

Postby Blake_Katsev_2E » Tue Feb 14, 2017 9:34 am

Does anybody know what the right answer was to the question about two crystals at 0K? it said that there was one crystal of CO and N2, and asked which would have a higher entropy.

Amy_Bugwadia_3I
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Re: Quiz one answer

Postby Amy_Bugwadia_3I » Tue Feb 14, 2017 10:45 am

Whenever a problem gives you something about 0K, it means that they're asking about residual entropy instead of standard molar entropy. Residual entropy has to do with degeneracy (W), specifically the following equation: S = Kb * ln(W). This equation shows that S is directly proportional to W (that is, when one increases, the other does as well). Degeneracy is essentially the number of microstates that a compound can exist in. CO has a greater number of potential microstates (positions it can exist in), so it thus has a higher entropy at 0 K. I believe that if they didn't specify 0 K and you were instead looking at standard molar entropy, the general trend is that with increasing mass, the entropy increases.


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