Atmospheric Pressure & Boiling Point of Water: 20 C

AI Thread Summary
To achieve a boiling point of water at 20°C, the atmospheric pressure must be significantly reduced, with calculations suggesting around 25 mbar. The Clausius-Clapeyron equation is essential for determining this relationship, requiring basic algebra to apply correctly. It's important to note that the calculation assumes pure water, as impurities like salt increase the boiling point. Initial calculations led to confusion, indicating the need for careful arithmetic. Accurate resources like steam tables can provide reliable data for these calculations.
ybhathena
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What does the atmospheric pressure have to be to make the boiling point of water 20 C?
 
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Google "Clausius-Clapeyron equation" and apply it...
 


Oh ok that seems to be what I need. Its a little bit advanced, could you explain the general idea of how to use this formula? I am a bit new
 


Hmm... Well that would be a very involved answer. You should be able to handle it if you know basic algebra. I'm assuming you were given the values to plug in. Also it assumes that it's pure water. Impurities such as salt require the chemical process to first break the hydrogen bonds making water boil at a higher temperature.

I did it for you quickly and got an an answer of 18,900m rounded.

Edit: Actually that can't be correct. That's the limit where water boils at the internal temperature of a human, 37 C. I must have messed up my arithmetic.
 
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