The pipet was calibrated to deliver the correct volume with this liquid remaining. Do no blow this remaining liquid from the pipet. 18.1.a.6.There may be some liquid remaining in the pipet tip. Allow the pipet to drain into the container and touch off any last drop on the pipet side of the glassware. 18.1.a.5.When the liquid level is at the correct place, move the pipet tip to the glassware where you want the liquid delivered and release your finger. Push the side button to allow your pipet to drain. If using a rolling pipet top, there is no need to remove the top. Now allow the liquid level to drop to the required level by slowly allowing air to enter the pipet by a controlled lifting of the finger that is covering the end of the pipet. If using an atomizer bulb: remove the bulb while simultaneously covering the tip of the pipet with your finger. 18.1.a.4.Once again, draw in the liquid to be measured above the calibration line in the pipet.
Dispose of this first amount of liquid into a waste beaker. Be careful not to draw the liquid into the bulb. Keep the pipet tip submerged to avoid air bubble entry. 18.1.a.3.Place the tip of the pipet in the liquid and draw the liquid into the pipet and above the calibration line. If using a rolling pipet top: Press the proper sized pipet top tightly onto the end of the pipet in order to create an airtight seal. You may want to lubricate the hole of the rubber bulb with a drop of deionized water. The bulb only needs to cover the end of the pipet to create an airtight seal, there is no need to push the pipet farther into the bulb. 18.1.a.2.If using an atomizer bulb: Compress the rubber bulb and place it carefully over the upper end of the pipet. 18.1.a.1.First clean and rinse your pipet with approved laboratory glassware cleaner, rinse with tab water and do a second rinse with deionized water.
The correct procedure for transferring liquid with a volumetric pipet.
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