Using a graduated pipette involves carefully drawing liquid up to a specific volume and then dispensing it accurately. Based on the provided reference (a YouTube video titled "Using a graduated pipette"), here's a breakdown of the process:
Steps for Using a Graduated Pipette
- Prepare: Place your glassware (e.g., beaker, flask) and the pipette into the liquid you want to measure.
- Aspirate Liquid: Use the dial (presumably referring to a pipette pump or bulb) to draw the liquid into the pipette.
- Fill to the Top Line: Carefully fill the pipette, ensuring the liquid reaches the desired volume marking (the "top line"). It's important to do this slowly for accuracy.
- Remove Pipette: Once the liquid is at the correct volume, slowly lift the pipette out of the liquid source.
Additional Considerations for Accurate Use
- Meniscus: Always read the volume at the bottom of the meniscus (the curved surface of the liquid).
- Cleanliness: Ensure the pipette is clean before use to avoid contamination.
- Vertical Position: Hold the pipette vertically when drawing up and dispensing the liquid for accurate volume delivery.
- Delivery: When dispensing, allow the liquid to drain naturally; do not force it out. A small amount of liquid may remain in the tip, which is accounted for in the pipette's calibration.
