17
LESSON 1: Goofy Putty
17
LESSON 1: Goofy Putty
You Be The Chemist Activity Guides | page
17You Be The Chemist Activity Guides | page 17You Be The Chemist Activity Guides | page 17
You Be The Chemist
®
Activity Guide | page 17
LESSON 1: Goofy Putty
ESTIMATED TIME Setup: 5–10 minutes | Procedure: 5–10 minutes
DESCRIPTION
Create a new “goofy” substance by mixing a borax
solution with glue.
OBJECTIVE
This lesson demonstrates the results of a chemical
reaction and compares and contrasts the properties of
mixtures and solutions. By making goofy putty,
students learn about measurement, mixtures, solutions,
physical changes, and chemical reactions. This lesson
can be extended to introduce polymers.
CONTENT TOPICS
Scientific inquiry; measurement; properties of matter;
chemical reactions; mixtures (solutions); polymers
MATERIALS
o White school glue
o Borax (found in the laundry detergent aisle)
o Measuring spoons
o Clear bowls, Ziploc
®
bags, or small cups
o Spoons
o Water
Always remember to use the appropriate safety
equipment when conducting your experiment.
Refer to the
Safety First
section in the
Resource Guide
on pages 421–423 for more detailed information about
safety in the classroom.
Jump ahead to page 20 to view the
Experimental Procedure.
OBSERVATION & RESEARCH
BACKGROUND
Most of the things around us are mixtures, like the air,
the ocean, lemonade, and pizza! A
mixture is made of
two or more substances that are combined physically.
When you combine glue with water, a glue-water
mixture is formed. Combining borax and water creates
a borax solution.
A solution is a specific type of mixture. A
solution
is a uniform mixture in which one or more substances
(solutes) are dissolved in another substance (solvent).
However, the mixture of glue and water is not a solution,
because the glue will not quite dissolve in the water.
Scientists sort matter by its physical and chemical
properties.
Physical properties can be observed by using
our senses and taking measurements. Some examples of
physical properties are color, shape, boiling point,
melting point, and density.
Chemical properties can be
identified by observing how a chemical reacts with other
substances. Some examples of chemical properties
include acidity, toxicity, and flammability. During the
experiment, students can observe the different physical
(and chemical) properties of the substances.
NATIONAL SCIENCE EDUCATION STANDARDS SUBJECT MATTER
This lesson applies both Dimension 1: Scientific and Engineering Practices and Dimension 2: Crosscutting Concepts
from A Framework for K–12 Science Education,established as a guide for the updated National Science Education
Standards. In addition, this lesson covers the following Disciplinary Core Ideas from that framework:
PS1.A: Structure and Properties of Matter
PS1.B: Chemical Reactions
ETS2.A: Interdependence of Science, Engineering, and Technology (see Analysis & Conclusion)
You Be The Chemist
®
Activity Guide | page 18
LESSON 1: Goofy Putty
When the glue mixture and borax solution are combined,
a change occurs. Matter often changes, and these changes
can be either physical or chemical. A
physical change is
any change in a substance’s form that does not change its
chemical makeup. The chemical formula of the substance
stays the same before and after the change. A
chemical
change
or chemical reaction is a change that takes place
when atoms of a substance are rearranged, and the bonds
between the atoms are broken or formed. During a
chemical reaction, the structure or composition of the
materials changes. When a chemical change is complete,
the resulting substance(s) is/are different from the original
substance(s).
By adding the borax solution to the glue mixture, you start
a chemical reaction. The glue molecules and the borax
molecules react with each other to create a stretchy, bouncy
new substance.
FORMULAS & EQUATIONS
Hydrous sodium borate (or sodium tetraborate decahydrate)
is commonly known as borax.
The chemical formula for borax is
Na
2
B
4
O
7
• 10H
2
O or Na
2
B
4
O
5
(OH)
4
• 8(H
2
O).
The structure of this formula means that each sodium borate
molecule has multiple water molecules attached to it.
White glue is primarily a mixture of water and polyvinyl
acetate (PVAc).
Water has the formula H
2
O.
The formula for PVAc is (C
4
H
6
O
2
)
n
. The n stands for
any number of molecules.
Because there are various PVAc molecules and because
different types of white glue have slightly different
compositions, it is difficult to provide the exact chemical
equation for the reaction of the borax solution and glue
mixture. Essentially during the reaction, borate ions from
the hydrous sodium borate cause the vinyl molecules in
the glue to form cross-linked bonds. The formation of
cross-linked bonds results in the creation of a new
substance made up of a long, flexible chain of molecules.
HYPOTHESIS
uMixing white school glue and borax
will create a new substance that has different
properties than the original substances.
CONNECT TO THE
YOU BE THE
CHEMIST
CHALLENGE
For additional background information, please
review CEF’s Challenge study materials online at
http://www.chemed.org/ybtc/challenge/study.aspx.
Additional information on mixtures, physical and
chemical properties, and chemical reactions can
be found in the Classification of Matter section of
CEF’s Passport to Science Exploration: The Core
of Chemistry.
Additional information on solutions can be found
in the Chemicals by Volume— Solutions section
of CEF’s Passport to Science Exploration:
Chemistry Connections.
Fun Fact
Initially, Silly Putty
®
was a
novelty item marketed toward
adults. In 1955, the market for the
item changed, and Silly Putty
®
became a popular toy among
kids between the ages of
6 and 12.
You Be The Chemist
®
Activity Guide | page 19
LESSON 1: Goofy Putty
LOWER GRADE LEVELS/BEGINNERS
Conduct the experiment as described on page 20, but
focus the lesson on describing and classifying matter.
Discuss physical properties in more detail and the
different uses of different substances.
Another option is to spend more time on the concepts of
mixtures, solutions, and chemical reactions. Use pictures
and have students write down or state their answers of
whether a certain substance is a solution or simply a
mixture. For example, show a picture of apple juice—
solution. Show a picture of chicken noodle soup—
mixture. After students complete this exercise, be sure to
remind them that solutions are a type of mixture.
Therefore, apple juice is a mixture and a solution.
Likewise, use the same method to go over physical and
chemical changes in more detail. For example, show a
picture of a pencil. Then show a picture of the pencil
broken—that’s a physical change. Next, show a picture of
cake batter and then a baked cake—that’s a chemical
change!
HIGHER GRADE LEVELS/ADVANCED STUDENTS
DESCRIPTION
Create a polymer by mixing a borax solution with glue.
OBJECTIVE
This lesson demonstrates the results of a chemical
reaction, compares and contrasts the properties of
mixtures and solutions, and introduces polymers.
By making goofy putty, students learn about
measurement, mixtures, solutions, physical changes,
and chemical reactions, as well as polymers.
OBSERVATION & RESEARCH
A molecule is the smallest particle of an element or
compound that maintains the chemical properties of that
element or compound. It is composed of two or more
atoms chemically bonded together by an exchange or
sharing of electrons. At the beginning of the 20
th
century,
chemists learned how to create special molecules by
combining many smaller molecules in a regular pattern.
These large molecules are called polymers.
Polymers are
long, chain-like molecules that are formed by connecting
many repeating units (monomer units). The most
common polymers are made of long chains of carbon
atoms. A
monomer is a single molecule capable of
combining with other similar molecules.
When you combine the glue and the borax solution, you
start a chemical reaction. A
chemical change or chemical
reaction
is a change that takes place when atoms of a
substance are rearranged, and the bonds between the
atoms are broken or formed. During a chemical reaction,
the structure or composition of the materials changes.
When a chemical change is complete, the resulting
substance(s) is/are different from the original
substance(s). When combined, the glue molecules and
the borax molecules react with each other and bond
together to make a tangled structure of long, flexible,
cross-linked chains. This giant molecule, a polymer, is
made up of thousands of smaller molecules. Like the
goofy putty created in this lesson, nylon and plastics
are also polymers.
Borate ions, provided by the borax (hydrous sodium
borate), cause the vinyl molecules in the glue to form
cross-linked bonds. The process of
cross-linking
continues to alter the physical properties of the
polymer. As more and more bonds are formed, the
characteristics of the polymer change. The polymer will
eventually become brittle as additional cross-linked
bonds are formed.
CONNECT TO THE
YOU BE THE
CHEMIST
CHALLENGE
For additional background information, please
review CEF’s Challenge study materials online at
http://www.chemed.org/ybtc/challenge/study.aspx.
Additional information on polymers can be found
in the Industrial Applications of Chemistry section
of CEF’s Passport to Science Exploration:
Chemistry Concepts in Action.
DIFFERENTIATION IN THE CLASSROOM
You Be The Chemist
®
Activity Guide | page 20
LESSON 1: Goofy Putty
NOTES
EXPERIMENTATION
As the students perform the experiment, challenge them
to identify the independent, dependent, and controlled
variables, as well as whether there is a control setup for
the experiment. (Hint: If the amount of borax added to
the glue and water mixture changes, do the results
change?) Review the information in the Scientific
Inquiry section on pages 14–16 to discuss variables.
EXPERIMENTAL PROCEDURE
1. Put one teaspoon of water into your cup or bowl.
Add one teaspoon of white glue and mix well.
(This may be a good time to discuss mixtures.)
2. In another cup or bowl, create your borax solution.
Mix one teaspoon of borax with four teaspoons of
water. Stir well. The solution will become saturated,
so all of the borax will not dissolve. (This may be
a good time to discuss the difference between
solutions and mixtures. You may also choose to
discuss saturation.)
3. Add one teaspoon of the borax solution to your
original cup of glue and water. Stir for 60 seconds.
4. Remove the substance and knead it with your
hands for one to two minutes.
During this experiment, you will be measuring
and mixing substances. If the measurements are
not exact, the experiment will not work correctly. If goofy
putty doesn’t form, see if the students can guess why and
then come up with a way to correct the problem, such as
adding more borax, adding more glue, or just starting over.
DATA COLLECTION
Have students record data in their science notebooks or
on the following activity sheet. For example, what
measurements did they use? What physical properties
did they observe? You can use the table and Venn diagram
provided in the activity sheet (or similar charts of your
own) for students to record their data.
You Be The Chemist
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Activity Guide | page 21
LESSON 1: Goofy Putty
ANALYSIS & CONCLUSION
Use the questions from the activity sheet or your own
questions to discuss the experimental data. Ask students
to determine whether they should accept or reject their
hypotheses. Review the information in the Scientific
Inquiry section on pages 14–16 to discuss valid and
invalid hypotheses.
ASSESSMENT/GOALS
Upon completion of this lesson, students should be able
to …
Apply a scientific inquiry process and perform an
experiment.
Understand the importance of measuring the correct
quantities to obtain desired results.
Compare and contrast mixtures and solutions.
Identify the physical properties of the substances
before and after the experiment.
Define and identify chemical reactions.
Differentiate between monomers and polymers
(see Differentiation in the Classroom).
MODIFICATIONS/EXTENSIONS
Modifications and extensions provide alternate methods
for performing the lesson or similar lessons. They also
introduce ways to expand on the content topics presented
and think beyond those topics. Use the following
examples or have a discussion to generate other ideas as
a class.
Add some color to your lesson! Students can make
their goofy putty different colors by adding food
coloring. They’ll simply add one drop of food
coloring to the glue mixture and stir until the color
seems to be spread throughout. Then, when they add
the borax solution to their colored glue mixture, their
goofy putty will turn out colorful as well! You can
also have some students add color after the goofy
putty has formed and they have shaped it into a ball.
Then, cut open one goofy putty ball that had color
added to the glue and water mixture, and cut open
another goofy putty ball that had color added once
the goofy putty ball was formed. The color added
later in the process is not absorbed all the way into
the ball. (You may want to have students use plastic
bags or gloves when adding color to avoid getting the
dye all over their hands.)
Challenge your students with the question: Is goofy
putty a solid or liquid? Let them discuss why they
think one way or the other. Then you can explain that
it is actually a viscoelastic liquid, which is a material
that demonstrates viscous (resistance to flow) and
elastic (solid) properties.
REAL-WORLD APPLICATIONS
If done correctly, the goofy putty should resemble
Silly Putty
®
. Have your students explore the history
of Silly Putty
®
, which was created when engineer
James Wright was attempting to create a synthetic
rubber for truck tires. Use this example to explain
that when doing experiments, scientists do not
always get the result they want, but they still may
discover something unique!
Chemical reactions are everywhere and so are
polymers! Polymers, like synthetic rubber, plastics,
Teflon
®
(a nonstick coating used for cooking products),
and Kevlar
®
(a synthetic fiber used in bullet-resistant
products) have been produced through chemical
reactions in laboratories.
COMMUNICATION
Discuss the results as a class and review the activity sheet.
Review the information in the Scientific Inquiry section on
pages 14–16 to discuss the importance of communication
to scientific progress.
You Be The Chemist
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Activity Guide | page 22
LESSON 1 ACTIVITY SHEET: Goofy Putty
OBSERVE & RESEARCH
1. Write down the materials you observe. ________________________________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
2. Predict how these materials may be used. ______________________________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
3. Define the following key terms. Then, provide an example of each by writing the example or drawing/pasting an
image of the example.
Term Definition Example (write or add image)
Mixture
Solution
Physical property
Chemical property
Physical change
Chemical reaction
4. Consider what will happen if white school glue, water, and borax are combined and why.
uWrite your hypothesis. ______________________________________________________________
______________________________________________________________________________________
______________________________________________________________________________________
You Be The Chemist Activity Guides | page 23
You Be The Chemist
®
Activity Guide | page 23
LESSON 1 ACTIVITY SHEET: Goofy Putty
3. What happens when you combine the borax solution and glue mixture? Explain how you know. ________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
ANALYZE & CONCLUDE
1. List the physical properties of each substance in the table below.
Glue Borax Goofy Putty
White...
2. Compare and contrast mixtures and solutions.
Mixtures Solutions
4. Is your hypothesis valid? Why or why not? If not, what would be your next steps? ____________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
PERFORM YOUR EXPERIMENT
1. Put one teaspoon of water into your cup or bowl. Add one teaspoon of white glue, and mix well.
2. In another cup or bowl, create your borax solution. Mix one teaspoon of borax with four teaspoons of water. Stir well.
3. Add one teaspoon of the borax solution to your original cup of glue and water. Stir for 60 seconds.
4. Remove the substance, and knead it with your hands for one to two minutes.
You Be The Chemist
®
Activity Guide | page 24
LESSON 1 ACTIVITY SHEET: Goofy Putty
2. List other substances that are polymers or are made of polymers. ________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
EXPAND YOUR KNOWLEDGE—ADVANCED
1. Define the following key terms. Then, provide an example of each by writing the example or drawing/pasting an
image of the example.
Term Definition Example (write or add image)
Molecule
Monomer
Polymer
You Be The Chemist
®
Activity Guide | page 25
LESSON 1 ACTIVITY SHEET: Goofy Putty
ANSWER KEY:
Below are suggested answers. Other answers may also be acceptable.
OBSERVE & RESEARCH
1. Write down the materials you observe. ________________________________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
2. Predict how these materials may be used. ______________________________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
3. Define the following key terms. Then, provide an example of each by writing the example or drawing/pasting an
image of the example.
Term Definition Example (write or add image)
Mixture
A physical combination of two or more substances
that can be physically separated.
Solution
A homogeneous (uniform) mixture in which one or
more substances (solutes) are dissolved in another
substance (solvent).
Physical property
A property of a substance that can be experienced
using the human senses and often detected
through a measuring device; physical properties
can be observed without reacting the substance
with some other substance.
Chemical property
A property of a substance that can be revealed by
the way the substance interacts with other
substances; describes an object’s “potential” to
undergo some chemical change or reaction due to
its composition.
Physical change
A change that alters the form or appearance of a
substance but does not change its chemical
makeup or create a new substance.
Chemical reaction
A change that takes place when atoms of one or
more substances are rearranged, and the bonds
between the atoms are broken or formed to
produce new substances; also known as a chemical
change.
4. Consider what will happen if white school glue, water, and borax are combined and why.
uWrite your hypothesis. ______________________________________________________________
______________________________________________________________________________________
______________________________________________________________________________________
Glue, borax, water, measuring spoons …
Mixing white school glue, water, and borax will create a new substance that has different
properties than the original substances.
Glue may be used to hold things together. Borax may be used to clean things.
Water may be used for drinking, cleaning, and many other things. The different materials may be combined to create something new.
Glue Borax Goofy Putty
2. Compare and contrast mixtures and solutions.
Mixtures Solutions
You Be The Chemist
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Activity Guide | page 26
3. What happens when you combine the borax solution and glue mixture? Explain how you know. ________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
ANALYZE & CONCLUDE
1. List the physical properties of each substance in the table below.
• White
• Sticky
• Viscous—it flows slowly
4. Is your hypothesis valid? Why or why not? If not, what would be your next steps? ____________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
• White
• Powdery
• Granular—grainy
• White (unless food coloring is added)
• Stretchy
• Can be molded into different shapes
• May or may not be uniform throughout
• Can be combined in various ways
• Solids, liquids, or gases
• Uniform throughout
• One substance is dissolved into another
• A type of mixture
• Generally liquids
• Made of two or more
substances combined
• The combined materials
retain their properties
and can be separated
physically
A chemical reaction
occurs. The resulting substance (the goofy putty) has different properties than the original substances.
Answer 1: Valid because the data support my hypothesis.
Answer 2: Invalid because the data do not support my hypothesis. I would reject my hypothesis and could form a new one, such as
PERFORM YOUR EXPERIMENT
1. Put one teaspoon of water into your cup or bowl. Add one teaspoon of white glue, and mix well.
2. In another cup or bowl, create your borax solution. Mix one teaspoon of borax with four teaspoons of water. Stir well.
3. Add one teaspoon of the borax solution to your original cup of glue and water. Stir for 60 seconds.
4. Remove the substance, and knead it with your hands for one to two minutes.
LESSON 1 ACTIVITY SHEET: Goofy Putty
ANSWER KEY:
Below are suggested answers. Other answers may also be acceptable.
2. List other substances that are polymers or are made of polymers. ________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
Plastic bottles, rubber bands, tires, polyester clothing,
nylon (tights), DNA, proteins …
EXPAND YOUR KNOWLEDGE—ADVANCED
Have students complete this section if you used the advanced differentiation information, or challenge them to find the answers to these
questions at home and discuss how these terms relate to the experiment in class the next day.
1. Define the following key terms. Then, provide an example of each by writing the example or drawing/pasting an
image of the example.
Term Definition Example (write or add image)
Molecule
The simplest structural unit of an element or compound that is
made up of atoms held together by chemical bonds and
maintains the chemical properties of the element or compound.
Monomer
A single molecule capable of combining with other similar
molecules to form a polymer.
Polymer
A large molecule formed by combining many smaller molecules
(monomers) in a regular pattern.
You Be The Chemist
®
Activity Guide | page 27
LESSON 1 ACTIVITY SHEET: Goofy Putty
ANSWER KEY:
Below are suggested answers. Other answers may also be acceptable.