Sarah Stadler
Chemistry Honors
Period 5
October 6, 2013
Beverage Density Lab
Background: The density of a pure substance is unique to its physical characteristics and can
therefore be used to identify a substance. In this lab we learned how to identify a solution
based on its density.
Density is measured with the ratio of mass over volume. (In this lab we used liquid
solutions so we calculated volume by volume displacement.) Once having measured a mass and
sample volume for each solution we could find the density. The density is the concentration of
a solute in a solution. If a solution were to have a higher amount of solute per solvent the
solution would be denser than the other. Now, because density is directly proportional to
concentration we can plot the density of a solution against the concentration of a solute on a
graph. This graph is called a calibration curve.
If we knew the density of a solution would we be able to find the concentration level?
Hypothesis:
If we can find the density of a solution, then we can use a calibration curve to find the
concentration of the solute.
Procedure:
1.
2.
3.
4.
5.
6.
7.
Find the mass of 10 mL of each of the 5 sugar solutions.
Calculate the density using this formula. D= M/V
Find the mass of 10 mL of each of the 6 beverages.
Calculate the density of all 6.
Look at nutrition labels for the 5 known beverages.
Find the amount of sugar in grams and the serving size.
Using the nutrition label off each beverage calculate the percent of sugar in each
beverage.
8. Going back to sugar solutions, create a graph with a y-intercept of density in g/mL and a
x-intercept of percent of sugar in a solution.
9. Draw a “best-fit” line through the plotted points.
10. Based on the density of each beverage, find the density of each on the y-intercept.
11. The x-value for where the beverage density intersects with the calibrated curve (or bestfit line) is the sugar percentage for that specific beverage.
12. Compared to the calculated percentage (off nutrition labels) calculate a percentage
error. (observed- true value)/true value = percentage error.
Sarah Stadler
Chemistry Honors
Period 5
October 6, 2013
Results:
Data Table A: Density of Reference Solutions
Solution
Sample Volume,
mL
Mass, g
Density, g/mL
0% Sugar
90634 g
10.00
.964 g/mL
5% Sugar
9.95 g
10.00
.995 g/mL
10% Sugar
10.13 g
10.00
1.013 g/mL
15% Sugar
10.35 g
10.00
1.035 g/mL
20% Sugar
10.58 g
10.00
1.058 g/mL
Data Table B: Beverage Density
Beverage
Sample Volume,
mL
Mass, g
Density, g/mL
Powerade
10.04 g
10.00
1.004 g/mL
Diet Pepsi
9.78 g
10.00
0.978 g/mL
Apple Juice
10.16 g
10.00
1.016 g/mL
Pepsi
10.19 g
10.00
1.019 g/mL
Lemonade
10.32 g
10.00
1.032 g/mL
Unknown
10.22 g
10.00
1.022 g/mL
Post-Lab: Results Table
Beverage
Measure
d
density,
g/mL
Percent sugar
(experimental
)
Amount of
sugar
(Nutrition
label)
Percent
sugar
(calculated
from
Percent
error
Sarah Stadler
Chemistry Honors
Period 5
October 6, 2013
Nutrition
label)
Powerade
1.004
g/mL
8.5%
21 g/ 360
mL
5.817%
46.12%
pepsi
0.978
g/mL
3%
0 g/ 355 mL
0%
3%
Apple Juice
1.016
g/mL
11%
27 g/ 240
mL
11.07%
0.6323%
Diet pepsi
1.019
g/mL
12%
41 g/ 355
mL
11.34%
5.82%
Lemonade
1.032
g/mL
14%
31 g/ 240
mL
12.52%
11.82%
Results Table:
Beverage
Experimental % sugar
8.5%
Powerade
3%
Diet Pepsi
Apple Juice
11%
12%
Pepsi
14%
Lemonade
Analysis:
Sarah Stadler
Chemistry Honors
Period 5
October 6, 2013
We learned prior to the lab that density of solutions is based on mass to volume, but
can also change with volume. Now, water is confusing for two reasons: water (0% sugar
solution) 1 mL of water has a mass of 1 gram, leaving the density of water at 1 g/ mL, and that
the volume of water changes in two different ways. With pure water the volume will decrease
from 0 degrees Celsius to 4 degrees Celsius, but then increase from 4 degrees and above. So
actually, water has a density of 1 g/ mL only at certain temperature.
When drawing a line through your plotted points it is not appropriate to connect-thedots because they are off the line for the error and that other things might be affecting the
density. This lab is not precise with beverages because there are other things in the solution
that affect the density.
Conclusion:
After carefully constructing a calibration curve we were successful at finding the
concentration of a solute based on its density.