last updated 12/30/2012

Transfer of liquids or solutions

In this lab course, students will use a syringe to draw the solution from a storage flask. The glass stopper is replaced by a rubber septum. The storage flask is connected to the inert gas line to generate a positive pressure in the solvent flask. The syringe material and needles should not react with the compound/solvent that is being transferred. Some solvents cause the rubber tip of the plunger to swell and make it impossible to move it. The syringe needle has to be clean and dry. Note that the plunger of the syringe should not been drawn past the halfway mark, particularly if reactive materials are transferred.

An alternative way of transferring solutions employs the use of stainless steel canula. This transfer takes usually a significant amount of time. The solution from one flask is forced through the needle into another flask by means of a pressure differential (by generating an overpressure in one flask and a slight vacuum in the other flask).