Chemical Determination of an Unknown Liquid
Purpose:
I will identify an unknown liquid by obtaining an average density & boiling point for my liquid and comparing them with the known densities & boiling points of liquids in the CRC handbook of Chemistry & Physics. I will perform these experiments using three different measuring tools (graduated cylinder, burette & pipette) to evaluate the precision of each one.
Results:
Density 1, 2 & 3 calculated by using graduated cylinder to obtain volume.
Density 4, 5 & 6 calculated by using volumetric pipette to obtain volume.
Density 7, 8 & 9 calculated by using burette to obtain volume.
All experimental values obtained have been included in this determination. Average density calculated numerically:
Average density = sum of all densities divided by total number of densities measured
Average density = (density 1 + density 2 + density 3 + density 4 + density 5 + density 6 + density 7 + density 8 + density 9) / 9
Average density = (0.771 g/mL + 0.778 g/mL + 0.786 g/mL + 0.788 g/mL + 0.7820 g/mL + 0.7820 g/mL + 0.7786 g/mL + 0.7737 g/mL + 0.7732 g/mL) / 9
Average density = 7.013 g/mL / 9 = 0.7792 g/mL
Average boiling point:
Average boiling point = sum of all boiling points divided by total number of boiling points measured
Average boiling point = (boiling point 1 + boiling point 2 + boiling point 3) / 3
Average boiling point = (63.0 °C + 62.9 °C + 63.2 °C) / 3
Average boiling point = 189.1 °C / 3
Average boiling point = 63.03 °C
Average density calculated graphically:
Per graph created in excel the equation of the best fit line is y = 0.7827x - 0.0851, per mathematics the slope for a formula of style y = mx + b is equal to m, thus the slope of the best fit line is 0.7827, since this graph plots a line of mass over volume then the slope of that line is the density which is 0.7827 g/mL. See attached paper for graph.
Unknown Liquid Code: D Average Boiling Point: 63.03 Average Density (Numerically): 0.7792 g/mL Average Density (Graphically):
I will identify an unknown liquid by obtaining an average density & boiling point for my liquid and comparing them with the known densities & boiling points of liquids in the CRC handbook of Chemistry & Physics. I will perform these experiments using three different measuring tools (graduated cylinder, burette & pipette) to evaluate the precision of each one.
Results:
Density 1, 2 & 3 calculated by using graduated cylinder to obtain volume.
Density 4, 5 & 6 calculated by using volumetric pipette to obtain volume.
Density 7, 8 & 9 calculated by using burette to obtain volume.
All experimental values obtained have been included in this determination. Average density calculated numerically:
Average density = sum of all densities divided by total number of densities measured
Average density = (density 1 + density 2 + density 3 + density 4 + density 5 + density 6 + density 7 + density 8 + density 9) / 9
Average density = (0.771 g/mL + 0.778 g/mL + 0.786 g/mL + 0.788 g/mL + 0.7820 g/mL + 0.7820 g/mL + 0.7786 g/mL + 0.7737 g/mL + 0.7732 g/mL) / 9
Average density = 7.013 g/mL / 9 = 0.7792 g/mL
Average boiling point:
Average boiling point = sum of all boiling points divided by total number of boiling points measured
Average boiling point = (boiling point 1 + boiling point 2 + boiling point 3) / 3
Average boiling point = (63.0 °C + 62.9 °C + 63.2 °C) / 3
Average boiling point = 189.1 °C / 3
Average boiling point = 63.03 °C
Average density calculated graphically:
Per graph created in excel the equation of the best fit line is y = 0.7827x - 0.0851, per mathematics the slope for a formula of style y = mx + b is equal to m, thus the slope of the best fit line is 0.7827, since this graph plots a line of mass over volume then the slope of that line is the density which is 0.7827 g/mL. See attached paper for graph.
Unknown Liquid Code: D Average Boiling Point: 63.03 Average Density (Numerically): 0.7792 g/mL Average Density (Graphically):
References: United States Environmental Protection Agency Technology Transfer Network Air Toxics Web Site, http://www.epa.gov/ttnatw01/hlthef/methanol.html (accessed May 16th, 2013). University of Manitoba CHEM 1300 Laboratory Manual "Physical Constants of Organic Compounds," in CRC Handbook of Chemistry and Physics, 92st ed. Haynes, W.A., Ed.; CRC Press: Boca Raton, FL, 2011; Chapter 3. (through CHEM 1300 Lab Manual) J. Olmstead, G. Williams, R.C. Burk; Chemistry, Canadian Edition.; John Wiley & Sons Canada, Ltd: Mississauga, Ontario , 2010; pp 72-79.