Lab Report: The Densities of Solutions and Solids Part A: The Precision of Volumetric Glassware Experimental Data Graduated Cylinder
Volumetric Pipet
Buret
Mass of Empty Beaker Mass of Beaker + Water Mass of Water only Actual Volume of Water used Density of Water
Share your three density values with all the students in your lab section, and record the results of the entire class in the table below (pay attention to significant figures). You should acquire at least ten density values for each type of volumetric glassware. Use an asterisks symbol (*) to denote which set of measurements you and your partner obtained.
Measurement
Class Density Values (in g/mL) obtained using: Graduated Cylinder
Volumetric Pipet
Buret
1 2 3 4 5 6 7 8 9 10 11 12 13 14
The Densities of Solutions and Solids
Page 1 of 5
Santa Monica College
Chemistry 11
Data Analysis 1) For each of the three density data sets, determine the average density and the standard deviation in the data set. Average
Circle any identified outliers in the three data sets on both your plot and in the data table. Then explain, using supporting calculations, how you identified these outliers.
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Now re-calculate the average and standard deviation for each data set, omitting the outliers. New Average
New Standard Deviation
Graduated Cylinder Volumetric Pipet Buret 4) Based on your analyses of the three data sets without the outliers, rank the volumetric glassware used from least to most precise. Briefly explain how you determined this order.
The Densities of Solutions and Solids
Page 2 of 5
Santa Monica College
Chemistry 11
Part B: The Densities of De-gassed Sodas Experimental Data Regular Soda Name of soda: Mass of Empty Flask: Data
Combined Mass of Flask + Soda
Initial Buret Reading: New Buret Reading
Total Mass of Soda
Total Volume of Soda
Density of Soda
1 2 3 4 5 6 Average density of regular soda: Diet Soda Name of soda: Mass of Empty Flask: Data
Combined Mass of Flask + Soda
Initial Buret Reading: New Buret Reading
Total Mass of Soda
Total Volume of Soda
Density of Soda
1 2 3 4 5 6 Average density of diet soda: Data Analysis 1) Which of the two sodas has the higher density? Suggest a possible reason for this result.
The Densities of Solutions and Solids
Page 3 of 5
Santa Monica College
Chemistry 11
Part C: The Density of an Unknown Metal Experimental Data ID Code of Assigned Metal: a. Mass of Empty Vial b. Mass of Vial + Metal c. Mass of Vial + Metal + Water d. Mass of Vial + Water e. Temperature of Water f. Density of Water at above Temperature Data Analysis 1) Using the data collected, calculate the density (in g/cm3) of your unknown metal. Show your work clearly, and circle your final result.
2) Your metal could be any of the following metals: zinc, titanium, lead, tungsten, aluminum, iron or nickel. Look up the true densities of these metals and identify your unknown metal. Suggested resources include your text, websites (e.g., www.webelements.com, www.chemicool.com) and the CRC Handbook of Chemistry and Physics. Identity of unknown metal: True density of metal: Source of density data: 3) Calculate the percent error between your experimental density and the true metal density.
The Densities of Solutions and Solids
Page 4 of 5
Santa Monica College
Chemistry 11
Questions 1) In Part A of this lab, you used your experimental results to rank the precision of three types of glassware from least to most precise. Did you expect these results? If yes, explain why. If no, explain why not, and give the order that you did expect.
2) Consider your density results for the diet soda in Part B of this lab. Clearly explain how they demonstrate that density is an intensive property.
3) Consider your results for Part C. Suppose your metal sample is hammered into the shape of a thin coin with a diameter of 8.62 cm. Determine the thickness (in mm) of this sheet. Use the measured metal mass and the true metal density for this calculation.
