November 28, 2024, 11:41:42 AM
Forum Rules: Read This Before Posting


Topic: entropy  (Read 4582 times)

0 Members and 1 Guest are viewing this topic.

Offline rleung

  • Full Member
  • ****
  • Posts: 186
  • Mole Snacks: +5/-5
  • I'm a mole!
entropy
« on: August 13, 2006, 03:07:28 PM »
Hi,

For a practice question in chemistry, it asks which of the following has the greatest entropy: O(g), O2(g), or O3(g).  The answer in the book was O(g), but I have always learned that, for molecules in the same state, entropy generally increases with increasing molecular complexity.  Hence, I would've chosen O3(g).  I even confirmed it in my textbook that has a table of values for entropy (O3(g) had the highest S value). 

Any thoughts?

Thanks.

Ryan

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27863
  • Mole Snacks: +1813/-412
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: entropy
« Reply #1 on: August 13, 2006, 04:03:52 PM »
IMHO something is wrong with the question. Are you talking about entropy of the signle molecule, or of the mole of molecules, or of the mole of oxygen atoms combined into molecules?
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline rleung

  • Full Member
  • ****
  • Posts: 186
  • Mole Snacks: +5/-5
  • I'm a mole!
Re: entropy
« Reply #2 on: August 15, 2006, 03:09:33 AM »
Ahh...I actually see where I went wrong now.  It said 5-g sample, so I guess O(g) would have the greatest number of moles, hence, greatest entropy, right?

Ryan

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27863
  • Mole Snacks: +1813/-412
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: entropy
« Reply #3 on: August 15, 2006, 03:56:21 AM »
Ahh...I actually see where I went wrong now.  It said 5-g sample, so I guess O(g) would have the greatest number of moles, hence, greatest entropy, right?

Sounds OK to me, but I am very narrowly specialized :)
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Sponsored Links