How to carry out a fractional distillation

Set up the apparatus as described Box 15.1 but insert the fractionating column between the distilling flask and the still-head. For extra stability, 

Apply the heat source slowly until the liquid begins to boil gently. Then slowjy increase the heat until the column is warmed up arid liquid is condensing from the thermometer bulb, but not distilling over. 

If the temperature is constant, increase the heat slightly until the first component distils oyer at a rate of about one drop every 2 seconds. Collect this distillate as the first fraction, as long as the temperature is constant (i.e. it does not vary more than 2-3 °C). Record the temperature rang e of the distillation. 

Increase the heat slowly and collect the intermediate fraction until the - temperature stabilizes again. Record the temperature range of the distillation. 

Change the receiving flask and collect the new fraction fone drop every 2 seconds) for as long as 

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