The procedure for preparing a volumetric pipet is the same as that for preparing a Mohr pipet. Before using a pipet, inspect it for chips or cracks and clean the pipet. Once the pipet is clean, rinse it several times with the solution to be transferred using the procedure below.
Draw a small portion of the liquid into the pipet. DO NOT allow the liquid you are drawing into the pipet to return to the original container - any solution returning to the original container will likely contaminate or dilute the liquid.
Hold the pipet horizontally and roll the pipet between your fingers so that the entire interior surface is rinsed (See Video 1). DO NOT allow the mouth of the pipet to get wet with the liquid.
Discard the rinse liquid into an appropriate waste container.
Prepare a solution of soapy water in a beaker. Draw the solution into the pipet, and wet the walls. Do not get the mouth of the pipet wet! Drain the wash water.
Put distilled water into another beaker. Draw distilled water
into the pipet and rinse out the soapy water. Rinse several times to remove all soap residue.
DO NOT attempt to fill the pipet by running water from the
tap directly into the mouth of the pipet.
How do you clean a pipet?