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JESMKS
2004-Sep-13, 05:30 PM
The atmospheric pressure on Venus is reported to be 90 times that of Earth
(90 bar) which is equivalent to 2700 inHg. The surface temperature on Venus is reported to 890 F. Varous boiling point calculaters on the internet show that water would boil at 5156 F. at a pressure of 2700 inHg. Other reports about Venus state that water would boil at 375 F., which is below the surface temperature and that all water has boiled away creating a desert. The boiling point calculaters also show that water would boil at 375 F. at a pressure of 118 inHg. What is the boiling point of water on Venus and how was it calculated?
Jack

alfchemist
2004-Sep-14, 04:42 AM
Hi JESMKS! are you interested to know if there's water in Venus or just to calculate the boiling point of water if the water is in Venus?

Try the Clausius-Clapeyron Equation:

ln(P2/P1) = [(enthalpy of vaporization of water) (T2-T1)]/R(T1T2)

where R = gas constant

P1=1atm
T1=100 deg celcius
P2=atm pressure in Venus
T2= new boiling point of water

Hope that helps.... :D

alfchemist
2004-Sep-14, 06:35 AM
Btw, convert all temperature units in absolute scale (Kelvin)

JESMKS
2004-Sep-15, 12:51 AM
I would like to know the temperature of the boiling point of water on Venus. Is it above 890 F. if so, there should be hot lakes on Venus. 375 F. seems awfully low for the boiling point under 90 bar pressure. Thanks for the reply.
Jack

ASEI
2004-Sep-15, 01:46 AM
According to my steam tables (engineering data describing the thermodynamic behaviour of water), water will boil at 579 degrees farenheit at a pressure of 1323 psia (equivalent to 90 bar).