tekkado
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Cold beaker should be hot?
So here in Oz its heating up and todays temp is 36 degrees in the shade. I poured a tiny amount of dcm into a beaker and placed it on a hot stone to
see if it would heat up at all or even boil? The temp is hot enough. The dcm was at room temp (didnt measure before hand) and now the flask is
actually quite cold where the dcm is. What would be the reason for this? It's becoming less cold now but thought it strange to happen.
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deltaH
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Evaporation of the DCM causes cooling. Google evaporative cooling... one of the oldest methods of air conditioning 
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tekkado
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Quote: Originally posted by deltaH  | | Evaporation of the DCM causes cooling. Google evaporative cooling... one of the oldest methods of air conditioning |
Ah true. Thanks for that 
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j_sum1
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I'm disenjoying the heat at present. Some of that evaporative cooling sounds like a good idea about now.
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Deathunter88
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| Quote: Originally posted by deltaH | | Evaporation of the DCM causes cooling. Google evaporative cooling... one of the oldest methods of air conditioning |
You can test that for yourself, squirt about 1ml of acetone or DCM onto the back of your hand and you will feel how cold it gets. Another way is to
put a drop of DCM on the bulb of a thermometer. The temperature reading on the thermometer should drop.
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tekkado
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Just from the talk. Is DCM an ideal candidate for this or would any solvent under the conditions act the same?
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tekkado
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| Quote: Originally posted by j_sum1 | | I'm disenjoying the heat at present. Some of that evaporative cooling sounds like a good idea about now. |
Straya.....haha i long for the cold.
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deltaH
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The lower the boiling point of the solvent, the colder it can get by evaporative cooling. DCM is a pretty good candidate because of that.
When I was young and inexperienced, I once filtered an organic product from DCM under suction and in the open, the evaporative cooling of the filter
cake caused ice crystals to form on top of the product because it got so cold. I was pretty mad because I now had a pretty wet product after it
thawed. 
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tekkado
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| Quote: Originally posted by j_sum1 | | I'm disenjoying the heat at present. Some of that evaporative cooling sounds like a good idea about now. |
Straya.....haha i long for the cold.
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Texium
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Thread Moved
22-12-2015 at 08:12 |
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