How to set up the apparatus for reflux with mechanical stirring

1 Clamp h multineck flask to a heavy support stand 

Slide a piece of rubber pressure tubing (about 40 mm long) half-way onto the drive shaft of the 

Very carefully line up the centre of the pressure tubing on the motor with the centre of the stirring rod and ensure that the drive shaft, stirring rod, 

Lift the stirring rod and slide it into the rubber tubing, about 10 mm, and then raise the flask so that the stirrer paddle is about 2 rnm above the bottom of the flask. Finally tighten all the clamps firmly. 

Make sure that the stirrer motor speed control is set to the mmimum speed or zero. Switch on the poiiver and turn the speed control to. the lowest setting. If the stirrer turns smoothly and slowly, all is well. You can increase the speed to check for 

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