Vaporizing ethanol from liquid What is going on here http://youtu.be/LQFmKPA-iAg
Is ethanol leaving the liquid? If so, why?
Does the pressure add energy to the ethanol molecules causing them to gasify and move rapidly near border of gas/liquid and rapid depressurization allows it to escape the liquid and turn back liquid, this time as mist/vapor?
Is the added pressure needed? Would same thing happen if we'd rapidly depressurize it regardless what is starting pressure?
 A: The partial pressure of ethanol in the air space above the beer would be approximately given by Raoult's Law. The vapour pressure of ethanol at 20°C is about 5.4kPa and water at the same temperature is 2.3kPa. The percentage by volume of ethanol in Budweiser is 5%, which is about 4% by weight or a mole fraction of 0.016. So the partial pressure of the ethanol vapour is about 87Pa. This corresponds to about 1 milligram of ethanol per litre of air. You would have to inhale a very large amount of the vapour to get drunk.
Note that this calculation does not (at least to a first approximation) depend on the partial pressure of other gases like nitrogen and oxygen (i.e. air) so pumping air into the bottle will not affect the amount of ethanol in the vapor above it and will not increase the amount of ethanol you can inhale.
The gentleman in the video appears to be having a good time, but it is unlikely to be due to inhalation of alcohol. If his intoxication is anything other than psychosomatic it's probably due to dizziness brought on by hyperventilation.
I would just drink the beer.
A: Is ethanol leaving the liquid?
Yes
Does the pressure add energy to the ethanol molecules causing them to gasify and move rapidly near border of gas/liquid and rapid depressurization allows it to escape the liquid and turn back liquid, this time as mist/vapor?
No
Is the added pressure needed?
No
Would same thing happen if we'd rapidly depressurize it regardless what is starting pressure?
Yes
Now the explanation of the phenomenon taking place in the video is:
The boiling point of any liquid depends on the pressure of the surroundings. By pumping the plastic bottle with air, the guy in the video is increasing the pressure inside the bottle. After this when the cork is suddenly removed the air rushes out rapidly from the bottle into the atmosphere. Due to the inertia effect of the moving air more air rushes out of the bottle that it normally should. This causes rapid depressurization resulting in a partial vacuum. This reduces the boiling point of ethanol resulting in vaporization of ethanol(white vapors).
So the same phenomenon can be obtained by rapidly depressurizing the bottle by some other means.
