Report: Experiment 1
Calibration of Volumetric Equipment
(Your name and section here)
Micropipette
Assigned micropipette number:
Temperature of water: 21.9°C
Density at this temperature: 0.997792 g/mL
(average vol. delivered + std. dev.)
(% relative uncertainty)
1.000 mL = 1.021 ± 0.003 mL
0.3%
0.500 mL = 0.504 ± 0.002 mL
0.4%
0.100 mL = 0.150 ± 0.004 mL
3%
Volumetric pipette
Temperature of water: 22.2°C
5.00 mL =
Density at this temperature 0.997724 g/mL
5 ± 1 mL
20%
50 mL buret
Buret Calibration Plot
2
Correction (mL)
1,5
1
0,5
0
-0,5
-1
-1,5
-2
0
10
20
30
40
50
60
Volume delivered (mL)
Questions
1. What is the significance of the difference between the average delivered volumes from your
pipettes and the assigned volume? (What is the term for this difference?) The term for the
difference between the average delivered volumes from the pipettes and the assigned volume is
called the absolute error. This difference is important because it is a measure of accuracy for
multiple measurements.
2. Another student used the same buret that you calibrated today in lab and read the initial volume
to be 10.00 mL. Then the student dispensed the solution such that the meniscus gave a final
volume of 30.00 mL. Using your calibration graph, determine the exact volume of liquid that the
student dispensed.
The student dispensed 21.23 mL of liquid because the correction factor for 20.00 mL is 1.23 mL.