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What is the heat of formation of water vapor?

  1. Dec 4, 2003 #1
    At standard temperature and pressure, what is the heat of formation of water vapor?
  2. jcsd
  3. Dec 4, 2003 #2


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    Heat of formation for
    H2O from H2 and O2 is -68.32 Kcal/Mol

    The latent heat of evaporation is -600 ca/g
  4. Dec 4, 2003 #3
    Heat of formation for a mole of water vapor: -241.82 kJ
  5. Dec 4, 2003 #4


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    How is this a brain teaser? And the phrase "at standard temperature" seems very odd to me in this circumstance, but it's been a while since I've considered this sort of stuff.

    - Warren
  6. Dec 4, 2003 #5
    too late, but i would say its -241.8 KJ/mol of H2O(g) produced , which is the same as meteor's answer.
    Last edited: Dec 4, 2003
  7. Dec 5, 2003 #6
    NateTG with the point!
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