There's a real problem separating alcohol from water, that you learn about when you reach more advanced levels of chemistry. I assume, for the purposes of the problem, that you wish to recover the two components.
Most alcohols and water are infinitely miscible. That means that they will not separate into layers. This is not universally true, but for most cases it applies. This means that no physical mechanism will achieve your purpose.
In most cases, when you have two liquids that mix, the way to separate them is through a fractional distillation -- put the mixture in a three-neck boiling flask with some boiling chips, add a distillation column to the top, with a condenser leading off to the side into a collection flask. In some cases, it might help to apply a vacuum to the system, reducing the boiling points and making it easier to perform the distillation. Heat carefully and watch out for any flammable vapors -- best to use an oil bath or electric heater.
But the real problem is that water and alcohol generally form an azeotrope -- this means that you can distill away part of the lower boiling point liquid (usually the alcohol), but at some point you will reach a stable mixture -- the azeotrope -- at which point you can boil it all day, and the stuff that comes out the condenser has exactly the same composition as the liquid in the boiling flask, and there's nothing you can do to separate it further. For example, the azeotrope for water and ethanol boils at 78.32°C, and consists of 96% (by weight) water and 4% ethanol.
One of the other posters suggested burning the alcohol off the top -- but you run itno the same problem -- you can burn off most of the alcohol, but you will never achieve 100% separation, and you are not recovering the alcohol. Freezing (differential crystallization) runs into the same problem once again -- you can't achieve complete separation.
2006-09-05 13:43:16
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answer #1
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answered by Dave_Stark 7
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Alcohol is produced by yeast during the process of fermentation. The other product of fermentation is carbon dioxide, which is the gas that can make beer bottles explode or blow their tops off. The amount of alcohol in the finished liquid depends on how much sugar there was at the beginning for the yeast to convert into alcohol. In beer, the alcohol is generally 3% to 12% (6 to 24 proof) and usually about 4% to 6% (8 to 12 proof). Depending on the strain of yeast, wines top out at about 14% to 16% (28 to 32 proof), because that is the point in the fermentation process where the alcohol concentration denatures the yeast. Since the 1990s, a few alcohol-tolerant 'superyeast' strains have become commercially available, which can ferment up to 20%. [2]
Very few microorganisms can live in alcoholic solutions. The main three are yeast, Brettanomyces, and Acetobacter. In what is essentially disinfection, yeast keeps multiplying as long as there is sugar to "eat", gradually increasing the alcoholic content of the solution and killing off all other microorganisms, and eventually themselves. There are "fortified" wines with a higher alcohol concentration than that because stronger alcohol has been mixed with them. As this is usually done before fermentation is complete, these products contain a much higher quantity of sugar and therefore are typically quite sweet.
Stronger liquors are distilled after fermentation is complete to separate the alcoholic liquid from the remains of the grain, fruit, or whatever it was made from. The idea of distillation is that a mixture of liquids is heated, the one with the lowest boiling point will evaporate (or "boil off") first, and then the one with the next lowest boiling point, and so on. The catch is that water and alcohol form a mixture (called an azeotrope) that has a lower boiling point than either one of them, so what distills off first is that mixture that is 95% alcohol and 5% water. Thus a distilled liquor cannot be stronger than 95% (190 proof); there are other techniques for separating liquids that can produce 100% ethanol (or "absolute alcohol"), but they are used only for scientific or industrial purposes. 100% ethanol does not stay 100% for very long, because it is hygroscopic and absorbs water out of the atmosphere.
2006-09-05 12:24:42
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answer #2
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answered by Anonymous
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Alcohol has a lower boiling point than water does. I would gently heat the mixture at a temperature below water's bp. The first part that boils off will be the alcohol. You will be left with water.
If you need to retain the alcohol, you'll have to catch it (inverted funnel or something similar) and condense it back to alcohol. Cool the alcohol in an ice bath and you should have a 95% alcohol/5% water mixture. I don't know how you will get the remaining 5% out in a school lab.
2006-09-05 12:33:13
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answer #3
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answered by ssbn598 5
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The salt, sand and water can form one mixture, the salt will dissolve in the water and the sand will not. steps in seperation 1. filter the mixture (sand can be extracted by filtration, which will leave the salt and water mixture) 2. Heat the solution gently in a flask with a stopper that has tubing running through it and into a separate flask. Continue until all water is gone and only salt remains. 3. filter the remaining wet salt then put the filter paper onto a watch glass and put irt close to heat for the excess water to evoperate. At the end you should have: 1. Sand on a filter paper 2. water in a separate flask 3. salt on a filter paper
2016-03-26 23:29:20
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answer #4
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answered by ? 4
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Alcohol evaporates (boils) at a lower temperature than water. Heat the water-alcohol mixture until the alcohol boils off from the water. Cool the vapor emitted, and it condenses into liquid alcohol. The device is called a still.
2006-09-05 12:21:09
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answer #5
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answered by Joseph G 3
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Through distillation equipment.
You heat the mixture. The alcohol comes off first.
2006-09-05 12:19:07
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answer #6
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answered by Anonymous
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Distillation...thats where "hard" alcohol comes from. Separating water from alcohol because alcohol boils at a lower temperature.
2006-09-05 12:35:56
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answer #7
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answered by Anonymous
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Try throwing a match into the mixture....then the alcohol will disappear and all that is left is water
2006-09-05 12:23:02
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answer #8
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answered by Anonymous
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since water and alcohol are liquids with different boiling points, distillation is the best method.
2006-09-06 02:55:58
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answer #9
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answered by woof! 2
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Put it in the freezer. The water will freeze and the alcohol won't.
2006-09-05 12:19:34
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answer #10
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answered by Peggy M 3
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