Investigation of Proper Experimental
Lab Techniques and Recording of Uncertainties
Chloe Yoo
October 3rd, 2014
Mrs. Mohuruk
Data Processing
Table 1: Station 1 - Density of Water Using 50ml Graduated Cylinder
Trial 1 | Trial 2 | Trial 3 | Trial 4 | |
Mass of Beaker (g) | 51.000.01 | 51.310.01 | 50.920.01 | 51.390.01 |
Mass of Beaker and Solution (g) | 60.530.01 | 60.030.01 | 60.470.01 | 60.840.01 |
Mass of Solution (g) | 9.530.02 | 8.720.02 | 9.550.02 | 9.450.02 |
Volume (mL) | 10.00.05 | 9.900.05 | 10.000.05 | 9.900.05 |
Density (g/mL) | 0.950.71% | 0.880.74% | 0.960.71% | 0.950.72% |
Uncertainty (%) | 0.71 | 0.74 | 0.71 | 0.72 |
Percent Error (%) | 5 | 12 | 4 | 5 |
Calculation Example (Trial 1):
Mass of Solution = (Mass of Beaker and Solution) - (Mass of Beaker)
= 60.53g0.01g - 51.00g0.01g = 9.530.0
Density of Solution = (Mass of Solution) (Volume of Solution)
* Change absolute certainty to relative uncertainty in order to do division.
9.53gñ0.02g = 9.53ñ0.21% g
10.0mL0.05mL = 10.000.50% mL
Density of Solution = 9.53ñ0.21%g 10.000.50%mL
= (9.5310.00) (0.21%+0.50%) = 1.050.71% g/mL
Percent Error = |(Measured Density - Accepted Density) Accepted Density| X 100%
*Accepted Density of Water = 1.00g/mL
Percent Error = |(0.95 - 1.00) 1.00| X 100% = |-0.05| X 100% = 5%
Table 2: Station 1 - Density of Water Using 10ml Graduated Cylinder
Trial 1 | Trial 2 | Trial 3 | Trial 4 | |
Mass of Beaker (g) | 50.080.01 | 51.550.01 | 50.790.01 | 50.770.01 |
Mass of Beaker and Solution (g) | 59.870.01 | 61.100.01 | 60.370.01 | 60.750.01 |
Mass of Solution (g) | 9.790.02 | 9.550.02 | 9.580.02 | 9.980.02 |
Volume (mL) | 10.000.05 | 9.900.05 | 9.900.05 | 10.000.05 |
Density (g/mL) | 0.980.70% | .960.72% | .970.72% | 1.000.70 |
Uncertainty (%) | 0.70 | 0.72 | 0.72 | 0.70 |
Percent Error (%) | 2 | 4 | 3 | 0 |
Calculation Example (Trial 1):
Mass of Solution = (Mass of Beaker and Solution) - (Mass of Beaker)
= 59.87g0.01g - 50.08g0.01g = 9.790.02
Density of Solution = (Mass of Solution) (Volume of Solution)
* Change absolute certainty to relative uncertainty...