Percent Sugar in Bubble Gum
Name:
______________________
Name of Partner:
______________________
Date Completed: ______________________
Date Due:
______________________
Block / Period:
Mr. Bannister
______________________
______________________
Introduction / Background:
A chemical is anything with a definite composition, which includes much of our everyday diet and consumables. Food,
beverages, candy, etc. all contain exact ratios of ingredients much like a simple recipe for chocolate chip cookies. Each batch
of cookies may contain 1 cup of sugar, 2 eggs, 1 cup butter, and so on. These ratios can be easily compared to the
stoichiometric ratios in a balanced chemical reaction. For example, consider the following balanced reaction:
1 C3H8 + 5 O2  3 CO2 + 4 H2O
For every 1 mole of propane that reacts, 5 moles of diatomic oxygen are required. This reaction then produces 3 moles of
carbon dioxide and 4 moles of water.
Purpose:
The purpose of this experiment is to determine the ratio of sugar per stick of gum. This information will then be used to
calculate the percentage (by mass) of sugar in a sample of gum.
Hypothesis:
Materials:
 5 pieces of sugared bubble gum
 Paper cup
 Balance
Procedure:
 Use a balance to determine the mass of a clean paper cup. Record the mass in your data table.
 Unwrap 5 pieces of bubble gum containing sugar and place them in the cup.
 Determine the mass of the cup and the gum. Record the mass in your data table.
 Each person in the group should chew a piece of gum to remove the sugar.
 After about 5 minutes, collect the chewed gum in the massed cup and wash your hands.
 Determine the mass of the cup and gum. Record it in your data table.
 Calculate the mass of sugar dissolved from the gum (original mass of gum – final mass of gum). Record the answer
in your data table.
 Calculate the percentage of sugar in the gum by dividing the mass of the dissolved sugar by the mass of the
unchewed gum and multiply by 100. Record the answer in your data table.
Results / Data:
Mass of Paper
Cup
Mass of Cup +
Gum
Mass of
Unchewed
Gum
Mass of Cup +
Chewed Gum
Mass of
Chewed Gum
Mass of Sugar
Percent of
Sugar
Discussions / Conclusions:
In addition to your own “personal” conclusions and reflections, you must include the following five post-lab questions. All
work is to be shown to receive full credit. Remember, anyone can do a lab but only a few can apply the knowledge to answer
questions with clear, articulated responses.
1.
What is the percent of sugar (percent composition)? **MUST show all calculations below**
= ____________% Sugar
2.
What is the molar mass of the sugar, C12H22O11? (Show your work below.)
= ______________g/mol
3.
Convert the mass of dissolved sugar to moles. (Show your work below.)
(Hint: mass lost in the measurements = mass of sugar dissolved in your saliva)
= _______________mols
4.
How many molecules of sugar are in the dissolved sugar? (Show you work below.)
(Hint: mass  moles  molecules)
= ___________molecules
Concept Check:
5.
If 5.84 grams of oxygen are consumed in the combustion of propane (you know this reaction), what mass of carbon
dioxide will be liberated, or produced?
Balanced chemical
reaction:
How many molecules (particles) of water will be produced??