This technique may be used for separating a mixture or purifying organic liquids when the components have differences in boiling points. In simple distillation, a liquid is boiled in a round bottomed flask and the vapors continue through the apparatus until they reach the condenser where they are cooled and reliquify. The liquid then continues through the vacuum adapter and is collected in a flask. Rubber bands are used around the distillation head to the top of the condenser and from the bottom of the condenser to the vacuum adapter. Cold water goes from the faucet into the condenser through the lower hose and exits out of the upper hose and into the drain.
Thin tubing is recommended.
Water flow through the system should be moderate. If the flow rate is too high, a hose could easily come off. The bulb of the thermometer is placed just below the distillation head for accurate reading of the vapor temperature. Generally, boiling stones are added to the boiling flask to ensure even boiling. Variacs are to be used for temperature control.