Latent heat in water vapor below boiling

[ceilidhdad]

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

 

[eigenperson]

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.