EXPERIMENT #1 DESIGN AND BUILD A CLOSED REACTION CHAMBER
Overview
The principle of conservation of mass states that matter is neither created nor destroyed in a chemical reaction.
The mass of reactant atoms is always equal to the mass of product atoms. This project focuses on a simple chemical
reaction, the combustion, or burning, or sucrose (table sugar). When heat is added to sucrose, hydrogen and oxygen atoms
are converted to water vapor, leaving solid carbon behind.
How can you measure the mass of these products? For this and many other chemical reactions, it is difficult to
gather evidence to support the law of conservation of mass. In this project, you will try to solve the problem of containing
the reactants and products of a chemical reaction. By measuring the masses of reactants and products, you will also
determine if mass is changed or remains the same after the chemical reaction.
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Project Rules
Design a solution for the problem of containing reactants and products in the combustion of sucrose. You must
use the materials your teacher provides or approves. Your design must be approved as well.
Using your design, build a closed reaction chamber.
Evaluate your chamber, test it for leaks, ad modify it as needed.
Carry out the combustion of sucrose in your completed reaction chamber. Observe, measure, and record the
results of the experiment.
Interpret your data and the pooled class data to determine whether mass is conserved in the reaction.
Present your findings in a visual display and oral presentation. In your presentation, you should include a
description of the chamber you designed and the design process, as well as your experimental results and
conclusions.
Project Hints
As you begin to design your reaction chamber, complete Project Worksheet 1. It will guide you in designing
and building an effective closed reaction chamber that is suitable for the sucrose combustion experiment.
At the beginning of the sucrose experiment, add a small amount of sucrose of known mass to the can through the
open bottle top. Record the mass of the sugar in the space provided in the Student Data Table on Project
Worksheet 2.
After adding the sucrose, cover the bottle top with a balloon, and then find the mass of the chamber plus sucrose
Record this value in the space provided in the Student Data Table.
When you burn the sucrose in the chamber, make sure the flame is centered beneath the can. Otherwise, the
adhesive between the can and the bottle may melt. Make sure the flame is not too high for the same reason.
Always use proper safety precautions when using a flame. Safety goggles and lab aprons should be worn at all
times.
Heat the sucrose until it turns black. Use tongs to handle the heated can or let the can cool before handling.
Measure the mass of the reaction chamber. Record the final mass in the Student Data Table on Worksheet 2.
Use the Class Data Table on Worksheet 2 to pool data from the entire class. Use a calculator to find the class
average. Also calculate the amount by which your change in mass differs from the class average. Record the
results of your calculation sin the spaces provided in the Student Data Table.
Use the data tables, or graphs made from the data tables, in your class presentation. Prepare for your
presentation by writing note cards that summarize how you designed your closed reaction chamber and any
problems you had to resolve; how you carried out the experiment and what the results were; and the conclusions
you drew about conservation of mass based on your data and the pooled class data.
Project Timeline
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Task
Complete Worksheet 1 and design chamber
Build, test, and modify chamber
Complete sucrose combustion experiment
Complete Worksheet 2 and draw conclusions
Make presentation to the class
Due Date
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CLOSED REACTION CHAMBER
Worksheet 1
This worksheet will walk you through the steps involved in making one type of closed reaction
chamber suitable for burning sucrose. The reaction chamber is shown below. Use the figure as
a guide.
1.
Obtain an empty metal food can. Also,
obtain an empty plastic water or soda bottle with
about the same diameter as the can. Wash the can
and bottle, and remove all the labels.
2.
Cut off the top third of the bottle with
scissors. Slide the bottle over the open end of the can
as in the figure. Fasten the bottle to the can in this
position using glue or tape.
3.
Test the seal between the can and bottle by
blowing into the top of the bottle and listening for
escaping air. Find and seal any leaks.
4.
Before adding the balloon to the bottle, add
the sugar for the sucrose combustion experiment.
Make sure you use the scale to measure the mass of the sugar first. Don’t forget to record
the mass in Student Data Table on Worksheet 2.
5. After adding the sugar, put the balloon over the mouth of the bottle. An inadequate seal
between the balloon and mouth of the bottle may result in a leaky chamber and loss of
mass. This can be avoided by placing a tight rubber band over the balloon around the
neck of the bottle.
6. Measure with the scale and record on Worksheet 2 the mass of the chamber plus sugar.
7. Set up the heat source as shown in the figure, and obtain your teacher’s permission to
carry out the experiment.
DATA TABLES FOR CLOSED REACTION CHAMBER EXPERIMENT
Worksheet 2
This worksheet consists of data tables to record your data and the data from the rest of the class. The tables also
have spaces for you to record individual changes in mass, the class average change in mass, and how your data
differ from the class average.
Initial mass of chamber and ballon (empty)___________
Student Data Table
Initial mass of
Final mass of
Mass of sugar
Change in
Data Source
chamber with
chamber with
(g)
mass (g)
reactants (g)
products (g)
Your data
Class average
Deviation from
class average
To assist you in figuring the class average, write the numbers below, as reported in class. Then average these
numbers by adding the columns and dividing by the number of data reported.
Mass of sugar
(g)
Lab Group 1
Lab Group 2
Lab Group 3
Lab Group 4
Lab Group 5
Lab Group 6
Lab Group 7
Lab Group 8
Lab Group 9
Total Mass
Number of
Groups
Average
Initial mass of
chamber with
reactants (g)
Final mass of
chamber with
products (g)
Change in
mass (g)
Presentation Outline
You only have 3 minutes, so make sure what you say is important. Read the below questions, discuss them as a lab
group, and write your answers in the spaces. You need to practice presenting, so START PRACTICING as if you were in
front of the class as soon as you have all your answers.
1. Talk about building your closed reaction chamber. What problems did you have? How
did you solve them? What did you find to be the best way to make your chamber?
2. What did your personal data show? Was your data in alignment with the LAW OF
CONSERVATION OF MATTER?
3. Talk about something you learned from this presentation.
4. What would you have done differently in your lab if given a second chance?