To separate a mixture of alcohol (ethanol) and water, you can use a process known as fractional distillation. This technique relies on the fact that the compounds in the mixture have different boiling points. Since ethanol boils at a lower temperature (78.5 degrees Celsius, or 173.3 degrees Fahrenheit) than water, the alcohol vaporizes while most of the water remains a liquid. A good distillation column will produce a mixture of 95 percent alcohol and 5 percent water. This ratio represents the most pure form of ethanol possible with distillation and is widely accepted as an industry standard.
Pour the ethanol/water mixture into the round-bottom flask.
Assemble the fractional distillation apparatus by attaching the fractioning column to the round-bottom flask. Attach the condenser to the fractioning column and place the distillate-capturing flask under it to capture the distillate.
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Place the Bunsen burner below the round-bottom flask and heat the mixture to above the boiling point of ethanol (about 80 degrees C).
Maintain the mixture at a constant temperature until the boiling has ceased. At this point, you have completed distillation.
Use protective glasses during the procedure. Have a fire extinguisher nearby as a safety precaution.