Latent heat in water vapor below boiling

AI Thread Summary
The latent heat of vaporization for water varies with temperature, decreasing as it approaches the critical temperature of approximately 374°C. At lower temperatures, such as 30°C and 60°C, the change in heat of vaporization is relatively small. Standard atmospheric pressure is assumed for these measurements. A linked PDF provides detailed values for the heat of vaporization at various temperatures from 0°C to the critical point. Understanding these variations is essential for applications involving evaporation and thermodynamics.
ceilidhdad
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Hi -

I'm a physics newbie so this is an elementary question, but I can't find the answer with a google search.

Water evaporates at a wide range of temperatures, what is the latent heat in the water vapor (in calories or Joules), for example, at 30°C, 60°C? Assume standard atmospheric pressure. Does it change at different ambient temperatures?

Thanks!

Adam
 
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The heat of vaporization does change with temperature, approaching 0 at the critical temperature (which for water is about 374 C). The rate of change is relatively small when the temperature is well below the critical temperature, though.

This page has a link to a PDF with the heat of vaporization at various temperatures between 0 C and the critical temperature.
 
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