What is the proper way to empty volumetric pipets?

The correct approach to emptying volumetric pipets is to let them drain completely without blowing out the remaining liquid. This method ensures that the volume measured is accurate and that the liquid inside the pipet is allowed to flow out naturally, allowing for complete drainage through gravity.

Volumetric pipets are calibrated to deliver a specific volume of liquid, and they are designed to hold the precise amount indicated on the calibration mark. After the liquid has been drawn into the pipet, it should simply be allowed to drain into the receiving vessel until no more liquid flows from the tip. This practice is essential for maintaining the integrity of the measurement, as blowing out any remaining liquid could introduce variability and lead to inaccuracies in the intended volume delivered.

In contrast, leaving a small amount in the pipet, blowing out the remaining liquid, or not emptying the pipet are practices that could compromise both the measurement accuracy and the pipet's intended use. Proper handling and usage of volumetric pipets are crucial in laboratory settings, especially when precise measurements are necessary for experiments or analyses.