What is the heat of formation of water vapor?

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Discussion Overview

The discussion centers around the heat of formation of water vapor, specifically at standard temperature and pressure. Participants explore different values and interpretations related to this thermodynamic property.

Discussion Character

  • Technical explanation, Debate/contested

Main Points Raised

  • One participant states that the heat of formation for H2O from H2 and O2 is -68.32 Kcal/Mol.
  • Another participant claims the heat of formation for a mole of water vapor is -241.82 kJ.
  • A different participant suggests that the heat of formation for water vapor is -241.8 KJ/mol, aligning with a previous response.
  • One participant questions the phrasing of "at standard temperature" and expresses confusion about its relevance.
  • A participant acknowledges another's point without elaborating on the content of that point.

Areas of Agreement / Disagreement

Multiple competing views remain regarding the specific values of the heat of formation of water vapor, and the discussion does not reach a consensus.

Contextual Notes

There are variations in the reported values for the heat of formation, and the discussion includes some ambiguity regarding the definition of "standard temperature."

Greg Bernhardt
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At standard temperature and pressure, what is the heat of formation of water vapor?
 
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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
 
Heat of formation for a mole of water vapor: -241.82 kJ
 
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
 
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:

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