Calibrating A Volumetric Pipette
Ryane Washington
Quantitative Analysis Lab
INTRODUCTION
This experiment was conducted to learn the relationship of 3 different types of pipettes and how to be accurate at measuring volumes of substances very accurately in quantitative analysis lab work. The accuracy of the measurement is the degree of closeness of measurements of a quantity’s actual volumes and the precision is the degree to which that are repeated measurements that are not changed show the same results.
Each of volumetric pipette has a different volume, to contain. To get the most accurate data, volumetric pipettes should be calibrated to get the volume that is actually delivered by the specific glassware. This calibration is accomplished by measuring the mass of water obtained by the glassware. Pipettes are calibrated to get specific volumes.
MATERIAL AND PROCEDURE
The materials used in the experiment were:-
10 mL volumetric pipette
25 mL volumetric pipette
50 mL volumetric flask
Distilled water
The procedure
Calibration of pipettes 5mL, 10 mL and 25 mL
a) An empty 50ml Erlenmeyer flask was weighed to the nearest milligram using an electronic weigh balance. The weigh balance that was used was an Adventure Pro Model AV313C registered from the State of Louisiana with the barcode number 338-00-58303. The Mass of the flask was 43919mg.
b) The 5ml pipette was filled to the line with distilled water. Distilled water was room temperature which was 70 degrees F
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