Still pots, receivers and fraction collectors

The components to be described next are the first and last links in the chain of distillation apparatus. The still pot contains the substance to be distilled and the receiver and the fraction collector take up the purified and fractionated distillate, respectively. 

For laboratory distillation ordinary standardized, round-bottomed flasks provided with ground joints are used. They may have short or long necks and nominal capacities up to 500 ml. The Engler (Fig. 235) and Saybolt flasks (TGL 0-12363) are examples of special devices designed for standardized distUlation techniques. In addition, a distilling flask with capacities from 25 to 1000 ml (TGL 0-12364) has been standardized (Fig. 313). 

Three-necked flask with thermometer well and sampling device 

The charge should be at most two-thirds of the volume of the flask in distillation at atmospheric pressure and not more than half in vacuum distillation. 

Flat-bottomed flask with ball joint 

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