Follow proper technique when using a pipet:
1. a volumetric pipet should be "blown out" to e...
Follow proper technique when using a pipet:
1. a volumetric pipet should be "blown out" to eject all liquid at the tip a volumetric pipet should not be "blown out" to eject all liquid at the tip.
2. volumetric pipets are calibrated in a manner that takes into account the solution which remains at the tip.
3. it is ok to pipet from the reagent bottle.
4. when the bottom of the meniscus coincides with the calibration mark, your pipet contains a precisely measured volume.
5. never pipet from the reagent bottle. pour some of the liquid you want to dispense into a small beaker.
6. do not force the pipet into the pipettor, be gentle. excessive force may cause the pipet to break and could potentially cut you while trying to insert or remove the pipet.
7. do not allow the solution to be drawn up into the pipettor. this will result in chemicals getting into the top of the pipet where you must put your finger.
8. never use your mouth to pull the liquid into a pipet. mouth pipetting is forbidden in the chemistry laboratory.
9. using the pipettor, you should turn the wheel on the pipette, draw up the solution until the meniscus is several centimeters above the calibration line, then quickly remove the pipette and put your thumb over the open hole of the pipet.
10.place the tip of the pipet in the solution which is to be drawn up.
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