ScienceNoob
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Vaccum Distillation Water BP Test
Hello there ScienceMadness I am a new hobby chemist trying to troubleshot my vaccum distillation setup. I have been reading about how atmospheric
pressure effects the Boiling Point of water and how darwin was able to boil water at room temperature at higher altitudes. I think this is the same as
what chemist try to to do when they use a vaccum distillation setup. The problem with my setup is water continually comes over at 100C. Tonight I am
trying to be patient and see if anything happens but I suspect nothing will happen because there is no vaccum click the link to see the setup http://youtu.be/2MamG4-NR5s
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DJF90
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You have no vacuum attached to your set-up and so water will only boil at its atmospheric boiling point, i.e. 100*C 1atm
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Hexavalent
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Are you serious, ScienceNoob??
Trying to do a vacuum distillation without a vacuum source of some kind is like trying to bake a cake without an oven. To get water to boil at RT, one
would need to go very high up into the atmosphere - quite probably higher than Everest. You say that you are new to chemistry; if I were you, without
being rude, I'd start out with something slightly simpler at your stage; why not try some aqueous test tube chemistry? You will learn a lot of the
basic principles of chemistry and lab technique qithout any major problems. Vacuum distillation is not a good starting point for a beginner.
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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BromicAcid
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Strictly going off calculations, the boiling point of water at the top of Everest (assuming ca. 0.333 atm) would be about 62°C, good thing too,
wouldn't want the people to start boiling now would we? To get water to come over at 25°C you need a pressure of about 56 mm Hg (by nomograph) which
would give an elevation of 17.339 km if the calculation on this page holds up. According to the Wiki article on the atmosphere this puts you out of the Troposphere and into the Stratosphere which
amusingly puts the average temperature between -60°C and 0°C.
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dchainy
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ROTFL! What else can I say?
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dchainy
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Oh crap do have something else.
I was reading a old book on making alch fuels and they're say to run the pump till there's a vac.
Then they say to shut the valve and turn off the pump.
But when I tried that it didn't work. I'm guessing the boiling created a increase in pressure.
So I've just been running the pump all night.
Oh yeah I'm talking about a still.
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