Sea Water Thermodynamic Properties?

AI Thread Summary
Thermodynamic properties of seawater, including specific heat and enthalpy, are crucial for designing solar desalinators. The density of seawater is approximately 1025 kg/m^3, and the specific heat is around 3850 J/(kg·C). There is a discussion regarding the accuracy of specific heat values, with some suggesting a potential unit issue compared to the specific heat of pure water. Variations in thermodynamic properties depend on salinity, which differs across various marine environments. For precise data, consulting historical research and reliable sources is recommended.
tanky322
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Im looking for thermodynamic properties of seawater, especially specific heat and enthalpy. I am designing a solar desalinator, and I am trying to determine the required amounts of energy to evaporate the water.

Is there a way in which I can determine the enthalpy of seawater by knowing the enthalpy of both salt and water?


Thank you
 
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Thank you!
 
Astronuc said:
The density of seawater is about 1025 kg/m^3 and the specific heat is about 3850 J/(kg C).

I think there is a unit issue with the specific heat of 3850 J/(Kg K), given that the specific heat of water is around 2200 KJ/(Kg K).

I just wanted to see if what I am saying here is making sense.


Thanks
 
Kaiser Engineering did an extensive research study for the government on the thermodynamic properties of seawater about 40 years ago. The properties vary with the salinity, which also varies in different parts of the seas. It is available from the Library of Congress
 
tanky322 said:
I think there is a unit issue with the specific heat of 3850 J/(Kg K), given that the specific heat of water is around 2200 KJ/(Kg K).
3850 is the right order of magnitude, depending on the salinity.

See here - no disclaimers required for this source:
http://www.kayelaby.npl.co.uk/general_physics/2_7/2_7_9.html
 
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