Why do larger molecules have higher entropies?

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  1. OSharp's Avatar
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    Why do larger molecules have higher entropies?
    Which of these solid substances is likely to have the greatest standard entropy? Use of
    the data booklet is not required.

    A SnO
    B SnO2
    C SnBr2
    D SnBr4

    the answer is D but to me this is counter intuitive as SnO will form the weakest Intermolecular forces so will be less ordered and thus have higher entropy?

    Please Help
  2. EierVonSatan's Avatar
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    Re: Why do larger molecules have higher entropies?
    The bigger the molecule the more internal parts it has (protons, neutrons, electrons) so the more different arrangements it can exist in => more disorder => higher entropy
  3. OSharp's Avatar
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    Re: Why do larger molecules have higher entropies?
    cheers, I am assuming that External state, i.e. (Gas>Liquid>Solid) has a greater effect than size?
  4. EierVonSatan's Avatar
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    Re: Why do larger molecules have higher entropies?
    (Original post by OSharp)
    cheers, I am assuming that External state, i.e. (Gas>Liquid>Solid) has a greater effect than size?
    Yes, but these are all solids at 298 K
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