3. The Sugar Content of Soft Drinks
Purpose
To determine the sugar content of some of the beverages you drink.
Overview
Sugar contributes more than any other solute to the density of soft drinks. Various soft drinks and juices
contain both sucrose (C12H22O11) and fructose (C6H12O6). Both sucrose and fructose have very similar aqueous
densities, so standard solutions of sucrose can be used as an indicator of the % sugar in various soft drinks. The
percent sugar standard solutions are on a mass/volume basis (g/100 mL of solution) and not a mass/mass basis
(g/100 g of solution). For example, a 5% sugar solution contains 5 g of sugar dissolved in 100mL of water. In
this experiment, you will prepare two of these solutions and determine the densities of 5 standard solutions. From
these densities you can make a standard calibration curve of density vs. % sugar (see Figure 1 for an example).
You will then determine the densities of various soft drinks. Using your standard calibration curve, you can find
the % sugar of these beverages and then calculate the number of grams of sugar in these drinks. Comparison
may be made between your experimentally determined values and the number of grams reported on the bottle or
can of each beverage.
Procedure
1. Prepare 2 standard sugar solutions, one 5.00% and one 10.00% sugar.
a. To prepare a 5.00% sugar solution, weigh out 5.00g of table sugar.
b. In a beaker, combine 5.00 g table sugar with approximately 75mL deionized H2O and stir until
completely dissolved.
c. Pour the solution into a 100 mL graduated cylinder and add deionized H2O up to a total volume of
100.0mL.
d. Transfer the 5.00% solution into a labeled beaker.
e. To prepare a 10% sugar solution, repeat steps b-d beginning with 10.00g sugar.
2. Standard solutions of 0%, 15.00%, 20.00% sugar have been previously prepared.
3. Determine the densities of the standard sugar solutions.
a. Pipeting 10.00 mL of each standard solution (0%, 5.00%, 10.00%, 15.00%, 20.00%) into a pre-
weighed container.
b. Find the total mass of the beaker and solution and record your data in the table provided.
c. Rinse the pipet after each solution.
d. Calculate the density based upon the measured mass of the solution and the volume.
4. Determine the densities of the available beverages by pipeting 10.00 mL of each soda into a weighed
container and weighing. Record your data in the table provided. Rinse the pipet after each solution.
Calculations
1. Calculate the density of each standard solution using the mass of the solution and the volume.
2. Graph density vs. % sugar. Draw the best straight line that “fits” these points. Your instructor may request
that you use a computer graphing program to graph these points and determine the best straight line “fit”
Chem 1111 Revision S7 Page 1 of 4
Purpose
To determine the sugar content of some of the beverages you drink.
Overview
Sugar contributes more than any other solute to the density of soft drinks. Various soft drinks and juices
contain both sucrose (C12H22O11) and fructose (C6H12O6). Both sucrose and fructose have very similar aqueous
densities, so standard solutions of sucrose can be used as an indicator of the % sugar in various soft drinks. The
percent sugar standard solutions are on a mass/volume basis (g/100 mL of solution) and not a mass/mass basis
(g/100 g of solution). For example, a 5% sugar solution contains 5 g of sugar dissolved in 100mL of water. In
this experiment, you will prepare two of these solutions and determine the densities of 5 standard solutions. From
these densities you can make a standard calibration curve of density vs. % sugar (see Figure 1 for an example).
You will then determine the densities of various soft drinks. Using your standard calibration curve, you can find
the % sugar of these beverages and then calculate the number of grams of sugar in these drinks. Comparison
may be made between your experimentally determined values and the number of grams reported on the bottle or
can of each beverage.
Procedure
1. Prepare 2 standard sugar solutions, one 5.00% and one 10.00% sugar.
a. To prepare a 5.00% sugar solution, weigh out 5.00g of table sugar.
b. In a beaker, combine 5.00 g table sugar with approximately 75mL deionized H2O and stir until
completely dissolved.
c. Pour the solution into a 100 mL graduated cylinder and add deionized H2O up to a total volume of
100.0mL.
d. Transfer the 5.00% solution into a labeled beaker.
e. To prepare a 10% sugar solution, repeat steps b-d beginning with 10.00g sugar.
2. Standard solutions of 0%, 15.00%, 20.00% sugar have been previously prepared.
3. Determine the densities of the standard sugar solutions.
a. Pipeting 10.00 mL of each standard solution (0%, 5.00%, 10.00%, 15.00%, 20.00%) into a pre-
weighed container.
b. Find the total mass of the beaker and solution and record your data in the table provided.
c. Rinse the pipet after each solution.
d. Calculate the density based upon the measured mass of the solution and the volume.
4. Determine the densities of the available beverages by pipeting 10.00 mL of each soda into a weighed
container and weighing. Record your data in the table provided. Rinse the pipet after each solution.
Calculations
1. Calculate the density of each standard solution using the mass of the solution and the volume.
2. Graph density vs. % sugar. Draw the best straight line that “fits” these points. Your instructor may request
that you use a computer graphing program to graph these points and determine the best straight line “fit”
Chem 1111 Revision S7 Page 1 of 4
