A rotary evaporator is a laboratory device used in the chemical laboratory to concentrate solutions, i.e. to evaporate the solvent. The rotary evaporator is one of the standard devices in the chemical laboratory. A rotary evaporator consists of a heating bath, a vapor tube with a standard ground joint, to the lower end of which the evaporating flask is attached, a cooler with a vacuum attachment and a collecting flask. The rotatable steam tube is guided into the cooler at its upper end by a shaft seal and can be set in rotation by means of a continuously adjustable motor. This entire structure is height-adjustable. In principle, this is a distillation apparatus whose evaporator flask can rotate about its longitudinal axis. The heat required for distillation is supplied by a heating bath into which the evaporating flask can be immersed by means of the height adjustment. The heating bath is usually filled with water, more rarely with oil to achieve higher working temperatures. It is also possible to evacuate the apparatus by means of a pump, i.e. to lower the internal pressure. The rotary evaporator is usually used in conjunction with a vacuum pump.