Why do F- and OH- have negative S values?

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F- and OH- ions exhibit negative standard entropy (S) values due to their unique thermodynamic properties, which are often relative to the arbitrary zero point assigned to the formation of H+ ions. This context is crucial as entropy values can vary based on the phase of matter, with the discussion primarily focusing on aqueous solutions. The negative S values for these ions suggest that they have lower entropy compared to other species, which typically have positive values. This phenomenon is not exclusive to F- and OH-, as other ions may also display negative entropy values under specific conditions, but they are among the most commonly referenced examples in thermodynamic studies. Understanding these values requires a grasp of the underlying principles of thermodynamics and the reference points used in calculations.
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Why do F- and OH- have negative S values? (Entropy)

And are they the only ones with negative S values?
 
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The question isn't too meaningful without a context: aqueous? gas phase? Homework?
 
aqueous; its not homework, I'm just curious. In my book, all the S values are positive except those two, I'm just wondering why.
 
Snoop around in the discussion of thermodynamic properties of ions a little more --- you'll find that they are relative to arbitrarily assigned zero values for H+ formation.
 
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