Measuring Volumes Using a Pipette and Burette
- Used to deliver a fixed volume of solution accurately
- Come in a variety of sizes
- wash with water (preferably distilled)
- Rinse with solution to be pipetted (3 times)
- Wind-up pipette fillers
- Plastic Bottle
- Mouth pipette (not advised)
- Using a plastic bottle suck the solution 2-3cm above the line.
- Close upper end of pipette with finger
- Let liquid run out slowly by relaxing the pressure of your finger and rotating it on the pipette until the bottom of the meniscus reaches the line.
- Drain it for 15 seconds, with the tip of the pipette in contact with the wall of the receiver vessel.
- Don’t blow out any remaining liquid
- If using a bulb or wind up pipette fillers then just pull solution until the bottom of the meniscus is on the line and drain as above
- Used to deliver a variable volume of solution
- Most commonly used for titrations
- Wash with water (preferably distilled)
- Rinse with small volume of solution to be used in the burette
- Clamp burette vertically and fill with solution using a funnel
- Remove funnel and run the solution through the tap until all air bubbles are removed
- Take measurement from bottom of meniscus unless using liquids in which it is hard to see and therefore read from the top. e.g. permanganate