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junglefish1
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Im sorry to ask such a question but I've been trying to understand the molecular reasons for why specific heat is high in some molecules but low in others. For example water has a specific heat of 4180 yet has a boiling point of 100 degrees Celsius but ethylene glycol (ethane 1,2 di-ol) has a boiling point of 194 degrees Celsius yet it has a specific heat of around 2200, so because of this it can't be due to bonds because you would think that if the bonds were the reason then ethylene glycol would have a specific heat due to its strong bonds. So then I found that its due to the amount of energy which they store, the degrees of freedom. Where there is 3 translational, 2 or 3 rotational depending whether the molecule is linear or non linear, thus the amount of degree of freedoms for vibration is 3N-5 or 6. But when that is found it gives larger molecules a larger number of degrees of freedom then smaller ones such as H20 or H2 which both have very high specific heat (especially H2 which is around 14.26 from memory) Anyways, my question is what am I missing basically? How come water has less way to store energy then ethylene glycol yet has a high specific heat?
Thanks to anyone that have time to spare to explain this, much appreciated as I have spent a while reading internet pages and both physics and chemistry textbooks without prevail. Cheers
Thanks to anyone that have time to spare to explain this, much appreciated as I have spent a while reading internet pages and both physics and chemistry textbooks without prevail. Cheers
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