CurriculumCurriculum - ASM Foundation · 2018. 3. 14. · Comments, criticisms, and suggestions are invited, and should be forwarded to ASM Materials Education Foundation. ASM Materials

CurriculumCurriculumCurriculumCurriculum

� 15 hours of student contact � 3 hours per day � 5 consecutive days � In-coming 6th, 7th and 8th graders

Debbie A. Goodwin Andrew G. Nydam

Materials DiscoveryMaterials DiscoveryMaterials DiscoveryMaterials Discovery

Encouraging middle school students to understand how materials shape

their world! Numerous studies have revealed an achievement gap in STEM knowledge and a reduced interest in STEM careers among middle school students. In 2014, ASM Materials Education Foundation launched a new program that focuses on engaging middle school children and exciting them about pursuing STEM education. The program encourages students to see the world around them as one in which science is transformed into technology through engineering. The primary goal of the program is to stimulate an interest in learning more about STEM as students move into high school. Through the Materials Discovery program, students will work in small groups and use hands-on experiments to explore concepts of physical science while learning to draw conclusions and apply basic engineering principles. The program focuses on common materials such as metals, ceramics, polymers, and composites. Research has concluded that this type of approach is a proven pathway that will engage and excite students about STEM subjects.

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Materials Discovery fills a hole in current middle school summer camp programming. It is chemistry-based

with engineering applications that complements the recent emphasis on robotics and physics dealing with

motion and energy. It also parallels with the new Maker Space programs allowing kids to make, manipulate

and test a variety of materials.

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This project is an initiative of the ASM Foundation’s Middle School CommitteeMiddle School CommitteeMiddle School CommitteeMiddle School Committee

Chair: Dr. Lyle H. Schwartz, FASMDr. Lyle H. Schwartz, FASMDr. Lyle H. Schwartz, FASMDr. Lyle H. Schwartz, FASM

Trustee and Past Chair, ASM Materials Education Foundation

Copyright © 2016 by

ASM International® All rights reserved

No part of this curriculum may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photo-copying, recording, or otherwise, without the written permission of the copyright owner.

Great care is taken in the compilation and production of this curriculum, but it should be made clear that NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, ARE GIVEN IN CONNECTION WITH THIS PUBLICATION. Although this information is believed to be accurate by ASM, ASM cannot guarantee that favorable results will be obtained from the use of this publication alone. This publication is intended for use by persons having technical skill, at their sole discretion and risk. Since the conditions of product or material use are outside of ASM’s control, ASM assumes no liability or obligation in connection with any use of this information. No claim of any kind, whether as to products or information in this publication, and whether or not based on negligence, shall be greater in amount than the purchase price of this product or publication in respect of which damages are claimed. THE REMEDY HEREBY PROVIDED SHALL BE THE EXCLUSIVE AND SOLE REMEDY OF BUYER, AND IN NO EVENT SHALL EITHER PARTY BE LIABLE FOR SPECIAL, INDIRECT, OR CONSEQUENTIAL DAMAGES WHETHER OR NOT CAUSED BY OR RESULTING FROM THE NEGLIGENCE OF SUCH PARTY. ASM does not endorse or guarantee the content contained in this curriculum. The conclusions and opinions contained in this curriculum and expressed by the instructor are those of the author and not those of ASM. ASM is not responsible for the use or misuse of the information contained herein. As with any material, evaluation of the material under end-use conditions prior to specification is essential. Therefore, specific testing under actual conditions is recommended.

Nothing contained in this curriculum shall be construed as a grant of any right of manufacture, sale, use, or reproduction, in connection with any method, process, apparatus, product, composition, or system, whether or not covered by letters patent, copyright, or trademark, and nothing contained in this curriculum shall be construed as a defense against any alleged infringement of letters patent, copyright, or trademark, or as a defense against liability for such infringement.

Comments, criticisms, and suggestions are invited, and should be forwarded to ASM Materials Education Foundation.

ASM Materials Education Foundation staff who worked on this project include Pergentina L. Deatherage.

Library of Congress Control Number: 2016930780

ISBN-13: 978-1-62708-114-6 EISBN: 978-1-62708-115-3

ASM International®

Materials Park, OH 44073-0002 asminternational.org

Printed in the United States of America

TABLE OF CONTENTSTABLE OF CONTENTSTABLE OF CONTENTSTABLE OF CONTENTS

DescriptionDescriptionDescriptionDescription Page NumberPage NumberPage NumberPage Number

About Materials DiscoveryAbout Materials DiscoveryAbout Materials DiscoveryAbout Materials Discovery IFCIFCIFCIFC

Curriculum OverviewCurriculum OverviewCurriculum OverviewCurriculum Overview 1-5

Monday Monday Monday Monday 6

Stretching Garbage Bags 7

Grow Beasts in Different Solutions 8-10

Cement Pucks 11-13

Growing Copper Crystals from Solution 14-15

Ice Melt Blocks Demonstration 16-17

TuesdayTuesdayTuesdayTuesday 18

Borax Crystals 19-20

Oobleck 21-22

WednesdayWednesdayWednesdayWednesday 23

Plastic Jug and Heat Gun 24-25

Water Gel Crystals 26-27

Gak and Slime 28-30

Thermoset Polymer - Eurocast in Silicone Molds 31-32

Shrinking Plastics 33-34

Polymer Powders 35-36

ThursdayThursdayThursdayThursday 37

Thermite in Yout Hand - Demonstration 38-39

Aluminum Can Liner 40-41

Steel Wool Corrosion 42-43

Metal Sand Casting 44-45

Fruit Battery 46-48

Developing the Activity Series 49-50

Brassing a Penny 51-53

FridayFridayFridayFriday 54

Separation Using Density 55-56

Pens Through Baggies of Water 57-58

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Materials DiscoveryMaterials DiscoveryMaterials DiscoveryMaterials Discovery

Overview of Middle School Camp CurriculumOverview of Middle School Camp CurriculumOverview of Middle School Camp CurriculumOverview of Middle School Camp Curriculum (15 hours)(15 hours)(15 hours)(15 hours)

Based on 15 hours of student contact, 3 hours per day for 5 consecutive days. Students are in-coming 6th, 7th and 8th graders ACTIVITIES INCLUDE:ACTIVITIES INCLUDE:ACTIVITIES INCLUDE:ACTIVITIES INCLUDE: DemonstrationDemonstrationDemonstrationDemonstration

• Done by teacher/leader • Can be done at the beginning or end of the day • Can also be used to get the group back together and refocused

Individual student labIndividual student labIndividual student labIndividual student lab

• Each student performs the lab by themselves • All students doing the same lab at the same time

Student partner labStudent partner labStudent partner labStudent partner lab

• Students work in pairs to complete a lab • All students doing the same lab at the same time

Small group labSmall group labSmall group labSmall group lab

• Students work in teams of 4 or 5 to complete a lab • All students doing the same lab at the same time

Station lab Station lab Station lab Station lab –––– individualindividualindividualindividual

• Students are in groups of 4 or 5 and rotate together between 4 stations • 4 different stations are going on at once • Need a teacher/leader at each station • Students in the group perform the lab at that station individually

Station lab Station lab Station lab Station lab ---- groupgroupgroupgroup

• Students are in groups of 4 or 5 and rotate together between 4 stations • 4 different stations are going on at once • Need a teacher/leader at each station • Students in the group perform the lab together

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MondayMondayMondayMonday Stretching garbage bags – student partner lab

• Warm-up lab to get the kids active and interacting • Students cut strips from garbage bags and have a contest to see who can stretch their

strip the most without it breaking • Demonstrates elasticity, plasticity and the effect of surface flaws • Uses measurement

Grow beasts in different solutions – individual student lab

• Set-up the lab on Monday, make observations each day, take home on Friday • Students grow hydrophilic alligators in 2L bottles (or other container) • Students use different types of solutions or different concentrations of salt water • Uses measurement

Cement pucks – making the control puck – small group lab

• Students make 3” diameter cement pucks with no reinforcement • Students will individually make reinforced cement pucks on Tuesday – making the

control puck in groups gives them practice

• All of the pucks will be tested on Friday – the non-reinforced group pucks serve as the control

• Uses measurement Test tube geology – individual student lab

• Students will grow copper crystals in plastic test tubes using a single replacement reaction between copper sulfate and iron nails

• Students will make observations daily • Students may take the copper home on Friday

Ice melt blocks - demonstration

• Discrepant event involving thermal conductivity • Ice is placed on blocks made of different materials • Students observe the melting characteristics

TuesdayTuesdayTuesdayTuesday Look at grow beasts and test tube geology – observing labs set up on Monday

• Write observations/make drawings/take pictures Borax crystals – individual student lab

• Make supersaturated borax solution and suspend shaped pipe cleaner • Observe growth of many crystals the rest of the week

Cement pucks – make reinforced pucks – individual student lab

• Students make a 3” cement puck and add reinforcement(s) of their choice • Students can bring reinforcement materials from home or the class can take a quick field

trip outside to gather materials

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• Pucks are drop tested on Friday to determine the strongest puck.

Oobleck - individual student lab

• Students make and investigate the properties of a non-Newtonian fluid made of cornstarch and water

WednesdayWednesdayWednesdayWednesday Polymer Theme DayPolymer Theme DayPolymer Theme DayPolymer Theme Day

Look at grow beasts, test tube geology, borax crystals

• Observing labs set up on Monday and Tuesday • Write observations/make drawings/take pictures

Heat gun and polymer bottles - demonstration

• Change the optical characteristics of an HDPE jug with heat and reshape it • Show polymer memory by heating and shrinking a PETE bottle

Set up water gel crystals – individual student lab

• Students make observations of a sodium polyacrylamide crystal and place it in water • The crystal will absorb the water and become invisible (will have the same index of

refraction as the water)

• Final observations will be made on Friday and the student may take it home Small groups of students rotate through the following 4 lab stations – a teacher/volunteer leader is in charge of each station: Gak and slime – station lab – individual

• The teacher demonstrates the effect of borax solution (a cross-linker) on a solution of Elmer’s glue and water - gak

• Students make colored slime out of polyvinyl alcohol solution and differing amounts of borax solution

• Students investigate and compare the properties of each batch of slime Eurocast/silicone molds – station lab – individual

• Students mix two resins to form a polyurethane thermoset and pour it into a silicone mold

• Silicone ice tray molds are used in a variety of shapes such as stars, hearts, dinosaurs, footballs – student get to choose one item to make

• The students will use their polyurethane piece on Thursday to make a mold for metal pouring

• The students will end up with a polymer piece and a metal piece of the same size and shape to take home with them

Shrinky-dinks – station lab - individual

• Students design an ornament, keychain, etc… out of a thermoplastic - polystyrene.

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• The thermoplastic is heated and it shrinks and becomes stiffer due to increased thickness

• This lab station illustrates polymer memory and thermoplastics

• Measurements and conservation of mass are involved. Polymer powders – water lock, instant snow, HDPE powder – station lab - individual

• Students investigate the properties of hydrophilic and hydrophobic polymer powders • Students brainstorm possible uses of these properties

ThursdayThursdayThursdayThursday Metal Metal Metal Metal Theme DayTheme DayTheme DayTheme Day



Rusty spheres and aluminum foil - demonstration

• Two rusty iron spheres and aluminum foil are used to demonstrate the thermite reaction • A single replacement reaction occurs between the iron oxide and aluminum when struck

with enough force – sparks and noise are produced! Aluminum can liner - demonstration

• The aluminum is eaten off of a sanded pop can when placed in hydrochloric acid – single replacement reaction

• The polymer liner is exposed • Shows that food cans and drink cans need protection from corrosion

Steel wool corrosion – small group lab

• Students place steel wool in different environments (solutions) and observe the rate of corrosion

• Shows the factors that need to be present for corrosion to occur Moon sand casting – station lab – individual

• Students use the Eurocast piece they made on Wednesday to make a mold out of moon sand

• The teacher/leader pours molten tin into the mold • Students clean their cooled metal piece and take home both the polymer and metal

pieces they made Fruit batteries – station lab - group

• Students use oranges, metal strips and a voltmeter to determine which combination gives them the most voltage

• This is a way of determining the activity series of metals which should parallel the results they get during the Activity Series lab

Activity series – station lab - group

• Students look for signs of chemical reaction between copper sulfate solution and six different metals

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• Students as a group rank the metals from most to least reactive – the results should parallel the outcome of the Fruit Batteries lab

Brassing a penny – station lab - individual

• Students zinc-plate a clean penny and then use a hot plate to make brass on the surface by solid state diffusion

• The students also explore The City of Materials website which includes a virtual lab and simulation of the experiment

FridayFridayFridayFriday Wrap up grow beasts, test tube geology, borax crystals

• Make final observations • Wrap-up discussion • Students may take them home

Wrap up water gel crystals

• Students make observations and measurements • Wrap-up discussion • Students may take them home

Polydensity tubes and comparing water/rubbing alcohol – individual student lab

• Students experiment with the cohesive nature of polar molecules (water) and nonpolar molecules (rubbing alcohol) using wax paper, droppers, toothpicks, and salt

• Students experiment with the density of different plastics using mixtures of rubbing alcohol, water and salt

• Students may take the polydensity tubes home Pens through baggies with water – individual student lab

• Students push an sharp pencil through a sandwich bag filled with water • The polymer chains in the bag “window” to allow the pencil through without leaking

Test cement pucks

• As a group, the students determine what constitutes failure of a cement puck, i.e. loss of 20% of mass, loss of 25% of volume, x # of cracks, etc….

• Students drop the pucks from increasing height until they reach the defined failure parameters

• Final discussion/analysis of what types and placement of reinforcement worked best

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MondayMondayMondayMonday Stretching garbage bags – student partner lab

• Warm-up lab to get the kids active and interacting • Students cut strips from garbage bags and have a contest to see who can stretch their

strip the most without it breaking • Demonstrates elasticity, plasticity and the effect of surface flaws • Uses measurement

Grow beasts in different solutions – individual student lab

• Set-up the lab on Monday, make observations each day, take home on Friday • Students grow hydrophilic alligators in 2L bottles (or other container) • Students use different types of solutions or different concentrations of salt water • Uses measurement

Cement pucks – making the control puck – small group lab

• Students make 3” diameter cement pucks with no reinforcement • Students will individually make reinforced cement pucks on Tuesday – making the

control puck in groups gives them practice

• All of the pucks will be tested on Friday – the non-reinforced group pucks serve as the control

• Uses measurement Test tube geology – individual student lab

• Students will grow copper crystals in plastic test tubes using a single replacement reaction between copper sulfate and iron nails

• Students will make observations daily • Students may take the copper home on Friday

Ice melt blocks - demonstration

• Discrepant event involving thermal conductivity • Ice is placed on blocks made of different materials • Students observe the melting characteristics

7

Stretching Garbage BagsStretching Garbage BagsStretching Garbage BagsStretching Garbage Bags OverviewOverviewOverviewOverview:::: Students work in groups of 2 or 3 to cut and stretch garbage bag strips. It is a good idea to have a variety of types and brands of garbage bags available for the students to choose from. Each team will cut and stretch a vertical strip and a horizontal strip. Preliminary data will be shared by all groups. Groups will be allowed to experiment and perfect their cutting and stretching technique. A final competition is held to determine which team can stretch their garbage bag strip the farthest. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• Garbage bags • Scissors • Rulers/meter sticks • Masking tape

Safety:Safety:Safety:Safety:

• Students should take care when using scissors Teacher Notes/Teacher Notes/Teacher Notes/Teacher Notes/Background/Background/Background/Background/Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:

• Different brands or types of garbage bags may be used for comparison. • Clean, sharp scissors work best. • Garbage bags are made of polymers. The polymer chains are randomly arranged in the

bag. • By gently pulling on the strips, the polymer chains align in the direction of the force

being applied. • As the chains align, the strength of the garbage bag strip increases. • The amount of stretch achieved can vary based on how the bag was manufactured. • Some bags will stretch more when the strip is cut vertically from the bag, others will

stretch more when cut horizontally. • A clean edge produces best results. Jagged edges or flaws will concentrate the stress

being applied and the bag will tear in that spot. • Percent elongation can be calculated to introduce more math.

Procedure:Procedure:Procedure:Procedure:

1. Use masking tape on the floor or table to mark the edges of a 24” x 2” rectangle. 2. Cut a vertical strip ANDANDANDAND a horizontal strip out of the garbage bag using the masking

tape template. 3. Carefully stretch each strip to obtain maximum length. 4. Measure and record the length of each strip. 5. Share data with all groups and discuss types of garbage bags and techniques used. 6. Allow 10 to 15 minutes for the teams to do further experimentation to improve their

results. 7. Each team makes and stretches one final strip as a competition.

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Grow Beasts in Different SolutionsGrow Beasts in Different SolutionsGrow Beasts in Different SolutionsGrow Beasts in Different Solutions OverviewOverviewOverviewOverview:::: Each student sets up their own grow beast in a growing chamber on Monday. Measurements and observations are recorded. Groups will have to decide what type of solution each student is using. Observations are made each day and measurements are taken mid-week and on Friday. The students take their grow beast home on Friday. A class discussion about the effects of the different types of solutions can be held mid-week and on Friday. MaterialsMaterialsMaterialsMaterials and Equipmentand Equipmentand Equipmentand Equipment::::

• Grow beast alligators (or other animals) – one for each student

• Empty 2L bottles with caps – one for each student • Plastic funnels – one for every four students • Distilled water – approximately 2 gallon • Tap water • Sugar – small bag • Salt – one container/box • Baking soda – one large box • Ruler or meter stick • Balances – one for every four students (can get by with just one – will slow things down) • Sharpie markers • Optional: other substances to make solutions to put the grow beasts into


• Students should wear safety glasses when making solutions TeacherTeacherTeacherTeacher NotesNotesNotesNotes////BackgrounBackgrounBackgrounBackgroundddd////Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:

• Put the students in groups of 4 or 5. • Each student in a group will grow their beast in a different solution (or distilled water) • Suggested liquids/solutions:

o Distilled water o Tap water o Saltwater o Sugar water o Baking soda water

• It is strongly suggested that each group has a gator growing in distilled water and one in tap water. The other solutions can vary.

• Students may choose the amount of solute to use. • Instead of using different solutes, the students could use different amounts of salt

instead. 0.9% is the salinity of human blood as a reference. • Students enjoy taking pictures each day if there is a means available.

• Students like to give their grow beasts a name. • Collect empty 2L bottles well in advance or request that students bring one to camp.

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• Plastic shoe boxes with lids or similar containers may be used instead of 2L bottles. • The alligators require a 2L bottle or container of similar size. Smaller grow beasts such

as frogs are available which can use smaller containers.

• Students will need a method of recording data – tablets, iPads, wall charts or lab notebooks are suggestions.

• The grow beasts are made of a super absorbent polymer that expands as water (fluid) is absorbed. These are not not not not to be confused with the capsules that contain sponges that expand when the capsule dissolves in a cup of water.

• The grow beasts will be too large to take out of the bottle after the first day. • Unless balances with large capacities are available, the solutions will need to be dumped

out to make mass measurements on Wednesday and Friday. Have additional empty 2L bottles available to make this easier. The solutions can be poured into the empty bottles while finding the mass of the grow beast and growing bottle. The solutions can be poured back into the growing bottle afterwards. One or two empty bottles per group is sufficient.

• Having a class discussion about how to measure the mass and length of the grow beast after it starts growing in the bottle is a good exercise in problem-solving and reaching consensus.


1. Make measurements of your alligator (grow beast) and record data: a. Mass in grams using a balance b. Length in cm using a ruler or meter stick

2. Place the grow beast into the clean, empty 2L bottle. If using the alligators you usually need to squeeze the legs towards the body to get the gator to go in.

3. Add approximately 2 liters of water to the bottle using a funnel. 4. Students using solutions need to mass out their solute - students can decide the amount

to use with guidance from the teachers. Record the type of solute and amount used. 5. Add the solute to the bottle, tighten the cap and shake to dissolve the solute. 6. Use permanent markers to write your name on the bottle. You can also write the initial

mass, length and type of liquid used on the bottle. 7. Place the bottles on their sides along a wall or the back of a counter where they will be

out of the way. 8. Visually check for growth each day. 9. If desired, measurements can be made mid-week.

a. The liquid will have to be poured out of the bottle so measurements can be made.

b. The liquid will need to be saved so it can go back into the bottle to continue growing the alligator.

c. The mass of an empty 2L bottle can be subtracted to get just the mass of the growing gator.

d. A ruler can be laid along the side of the bottle to measure the length. e. Pour the liquid back into the bottle to continue growth until the end of the week.

10. On the last day, final measurements can be made. a. If the students want to keep their beasts in the bottles to take home, then final

measurements can be made using the method described for mid-week.

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b. If the students want to take their beasts out of the bottles, the liquid will need to be emptied down a sink and scissors used to cut an opening in the bottle. Adults may need to do the cutting for safety reasons.

distilled water tap water

0.45% salt

water

0.9% salt

water

no water

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Cement PucksCement PucksCement PucksCement Pucks

OverviewOverviewOverviewOverview:::: This is a multiple day lab. Students work in groups of 3 or 4 the first day to make a non-reinforced cement puck to serve as a control for testing. On the second day, students work individually to make a cement puck reinforced with a material(s) of their own choosing. On the final day, the pucks are tested and the results analyzed.

Materials:Materials:Materials:Materials: • Portland Cement (at room temperature) • Water (at room temperature)

• Plastic Easter grass • Other fibers/materials to use as reinforcement

Equipment:Equipment:Equipment:Equipment:

• Styrofoam cups – for massing out cement • Disposable bowls (such as Styrofoam) – for mixing

• Plastic spoon • Scale • Duct tape • Vaseline • Cotton swabs • Graduated cylinder • Rims cut from large Styrofoam cups OROROROR PPPPVC rings (3” diameter, approximately 5/8”

width) SafetySafetySafetySafety:

• Cement/cement paste/mortar/concretes are caustic. Once the mixtures leaves dormancy the pH goes above 12. Avoid prolonged contact

• It does not hurt to get fresh paste on exposed skin; but it will dry out the skin. • Wear gloves if you are sensitive to high pH solutions • Cement paste will wash out of clothes • If any gets in someone’s eyes, wash out immediately • Students should wear safety glasses when massing out the cement • Students with sensitive skin might need to wear disposable plastic gloves

Teacher Notes/Teacher Notes/Teacher Notes/Teacher Notes/Background/Background/Background/Background/Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:

• PUT DUCT TAPE OVER YOUR DRAINS! • Cement paste/concrete will clog the drains and no; more water will not dilute it. • Don’t put ANY cement paste down the drains. • Have a 5 gallon or large plastic bowl with water for students to rinse their hands before

washing them in the sink. • Use good quality duct tape otherwise the molds will leak.

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• Cement is a brittle ceramic material. Reinforcement such as sand and gravel is added to cement to make concrete which is a composite. The reinforcement adds strength and helps stop the growth of cracks that develop in the cement.

Methodology Methodology Methodology Methodology –––– Day 1: Day 1: Day 1: Day 1: Students will make a plain cement puck in teams of 4 or 5. Each team will make one non-reinforced cement puck to serve as a control for testing. These should be made on the first day and will also serve as “practice”. The second day each student will make their own cement puck with reinforcement(s). The students can practice teamwork by dividing up tasks in making the non-reinforced cement puck, i.e. massing out the cement, preparing the mold, measuring out the water, stirring the cement. Tell the students that they will be making their own individual pucks the next day and that they can bring something from home to use as reinforcement. Or they can find something to use in the classroom or outdoors. Procedure:Procedure:Procedure:Procedure: Sample 1: plain cement paste (non-reinforced)

1. Enclose one side of the Styrofoam ring (or PVC ring) using duct tape. Make sure it is sealed.

2. Spread a light layer of Vaseline over the duct tape base to make it easier to demold the specimen after it hardens.

3. Pour 50 mL of water into the Styrofoam bowl. 4. Mass out 100 g of cement in the foam cup. 5. Gradually add cement powder to the water while stirring. 6. Mix and pour into the mold. 7. Label the specimen with the Team # or name. 8. Allow the cement to harden at least 24 hrs. 9. Demold the specimens.

MethodologyMethodologyMethodologyMethodology –––– Day 2Day 2Day 2Day 2:::: Each student will make their own cement puck using some type of reinforcement(s). The goal is to make the pucks more resistant to cracking and breaking when dropped. The students may bring materials from home or the instructor could take the students outside to find items to use. The students can choose to mix the reinforcement material(s) into the cement paste or layer them. Procedure:Procedure:Procedure:Procedure: Sample 2: reinforced cement paste Use the same procedure as sample 1 exceptexceptexceptexcept add Easter grass or some other reinforcement material. Record the type and amount of reinforcement material used and describe the placement of the material. TestingTestingTestingTesting –––– Final DayFinal DayFinal DayFinal Day

1. The students have to decide as a group what constitutes “failure” before testing begins. This discussion should occur prior to making the pucks. Examples of group decisions are: puck loses ¼ of its mass, puck loses ¼ of its volume, a crack grows all the way across the puck, etc…

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2. Place disk in plastic bag if you want to keep the broken pieces together. Standing over a hard surface (concrete or tile floor), drop the mortar specimens from equal heights. Make sure to drop the samples flat to ensure the pieces break. If testing indoors, it is a good idea to break open the bottom of a cardboard box and drop the pucks inside to contain the broken bits and pieces – this makes clean-up easier.

3. Observe the difference between the mortars and what influence the fibers or other reinforcements have over resistance to fracture.

Observations and AnalysisObservations and AnalysisObservations and AnalysisObservations and Analysis Record observations on how well each disk performs during the drop test. Things to look for:

• # of breaks/cracks • Length of breaks/cracks • # of pieces the disk broke into

Analyze which type of disk performs best. Include type and placement of reinforcement material. Extra Background Material:Extra Background Material:Extra Background Material:Extra Background Material: Discuss how cracks form and grow in brittle materials unless interrupted. Brittle materials have very poor strength in tension. Once a crack forms the fibers take the tension and help prevent the crack from spreading. Toughness is the area under the load vs. deflection curve (stress-strain curve). A brittle material just cracks and breaks (like glass). The fibers in a fiber-reinforced material help keep the cracks small so there is friction along the crack face and the fibers take some of the load. This load dispersion is good for materials under fast loading such as explosions. The fibers absorb some energy and prevent pieces from flying off creating secondary injuries. The military uses lots of fiber-reinforced materials from body armor to walls on bases. Discuss the different types of fibers. Birds use higher tensile strength grass fibers to reinforce the brittle mud in their nests. Ancient mud bricks were fiber-reinforced with straw. Concrete fibers can be steel, polypropylene (like Easter grass), nylon, carbon, or cellulose.

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Growing Copper Crystals from SolutionGrowing Copper Crystals from SolutionGrowing Copper Crystals from SolutionGrowing Copper Crystals from Solution

Overview:Overview:Overview:Overview: Students work individually to set up a single replacement reaction in a plastic test tube (preform). Observations are made daily and the students may take the copper crystals or entire set-up home on Friday. The concepts of chemical reactions, elements and compounds and the relative reactivity of metals may be discussed as the reaction progresses. MaterialsMaterialsMaterialsMaterials and Equipmentand Equipmentand Equipmentand Equipment::::

• Preform and cap – one per student • Preform racks – one per every 6 students or another holder for the preforms (test tubes)

• Copper II sulfate pentahydrate – medium crystals • Non-iodized salt – one box – poured into several small containers (ex. plastic cups) • Brights nails – 2” to 3” in length – two per student • Steel wool – used to clean the nails • Cotton balls or coffee filters • Plastic pitchers of water


• Students should wear safety glasses when measuring and pouring chemicals. • Copper sulfate is harmful if swallowed – if swallowed, provide water and call a physician. • In case of contact with copper sulfate, rinse the skin with water. • No food or drink should be allowed during this activity.

TeacherTeacherTeacherTeacher NotesNotesNotesNotes////Background/Background/Background/Background/Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:

• Each student will set-up their own test tube but can share test tube racks. • Cotton balls or coffee filters (filter paper) can be used to make the barrier layers.

• If using cotton balls, pull small pieces from a larger cotton ball. A separation between layers is needed but it should be a thin barrier layer.

• If using filter paper, cut disks the size of the interior diameter of the preform. The instructor may want to make these ahead of time as the students generally have difficulty making them. Or at least have some on hand for the students that are having trouble if they do it themselves.

• Set out labeled cups or beakers of copper sulfate and salt for the students to share in small groups.

• Students enjoy taking pictures each day if there is a means available.

• A hand lens or magnifier is useful for making observations during the activity.

• A single replacement reaction occurs in the preform. Iron (nail) is more reactive than copper so it will replace it in the solution forming pure copper crystals.

• CuSO4 + Fe Cu + FeSO4 • The lab mimics the formation of pure mineral copper deposits in Earth’s crust.

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• Air pockets sometimes form in the test tube. Inserting and then removing a thin copper wire down the inside of the test tube will often release the trapped air.


1. Pour approximately 1 to 2 cm (1/2 inch to 1 inch) of copper sulfate crystals into a preform (test tube). Students can use a small spoon or spatula and a funnel can help prevent spills.

2. Add enough water to cover the copper sulfate. 3. Place a small piece of cotton or disk of filter paper on top of the copper sulfate. A

pencil or stirring rod can be used to push it into place. 4. Place the same amount (depth) of salt (sodium chloride) into the preform (test tube) 5. Cover the salt layer with water. Pour slowly and gently to avoid stirring or mixing the

layers. 6. Add another small piece of cotton or filter paper disk. 7. Place two or three nails on top of the second barrier. 8. Add water to cover the nails. 9. Place the cap on the preform. Write student initials on the cap or preform with a

permanent marker. 10. Place the racks with the preforms in an area where they will not be disturbed. 11. Make observations every day. Make labeled drawings or take pictures. 12. On the final day students may take their preforms home. 13. If the students want to take the copper that formed out of the preform they may do so.

a. Slowly pour the contents of the preform into a plastic cup or beaker. b. Carefully separate the copper from the other solids using a spoon or some type

of probe. c. Remove the copper from the cup using a spoon. Gently rinse the copper with

water using an eyedropper or disposable pipette. d. Place the copper on a paper towel to dry.

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Ice Melt BlocksIce Melt BlocksIce Melt BlocksIce Melt Blocks DemonstrationDemonstrationDemonstrationDemonstration

Overview:Overview:Overview:Overview: This is a teacher demonstration with active student involvement. The demonstration involves the concept of thermal conductivity and heat transfer. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• Aluminum block - 3” X 3” painted black

• Polymer block - 3” X3” painted black

• Ice cubes

• Paper towels


• Aluminum is a very good thermal conductor. Polymers are poor thermal conductors.

• Heat flows from a material or object at a higher temperature to one at a lower temperature. Heat flows until they are the same temperature.

• The blocks will be at room temperature. Human body temperature will be higher than the blocks so heat will flow from your fingers into the blocks when you touch them.

• Aluminum is a very good thermal conductor so the heat that transfers from you to the block will flow throughout the block. Therefore heat will keep transferring into the block until the whole block is heated.

• Polymers are poor thermal conductors. As thermal energy flows from you to the block the heat is concentrated in the area you are touching – the heat does not flow to the entire block. Therefore the temperature of the block and your fingers will match more quickly.

• There will be a greater flow of heat energy into the aluminum block than the polymer block when you touch them. Thus the aluminum block gives the sensation of being colder than the polymer block when you first touch them even though they start out at the same temperature.

• The ice is colder than the blocks so heat will flow into the blocks. The students often predict that the “cold-feeling” (metal) block will not melt the ice as quickly as the “warmer-feeling” (polymer) block. It is a discrepant event for most students when the metal block melts the ice much quicker than the polymer block. Since the metal is a good thermal conductor the whole block will transfer heat to the ice thus melting it quickly.

• Heat flows from the polymer block into the ice where there is contact between the two. Since the polymer is a poor thermal conductor, heat does not flow from the entire block to the ice. Therefore the ice melts much more slowly.

• Students often think there is a difference in the two pieces of ice instead of the blocks. After the ice cube is half melted on the metal block, pick up the 2 pieces of ice and place them on the opposite block. The one that was melting quickly on the metal block will now practically stop melting on the polymer block. The one that was slowly melting on the polymer block will now quickly melt on the metal block. This should help direct

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the discussion to the difference between the blocks and the concept of thermal conductivity.

• Additional discussion can focus on practical applications of this concept: o How could you thaw frozen food more quickly? Place the frozen food on a metal

cookie sheet or in a metal sink. There have actually been “miracle thaw blocks”

sold on home shopping networks which are nothing more than a chunk of

aluminum.

o Why do they use aluminum in radiators and heat sinks for computers? Aluminum

transfers heat more efficiently and quickly than many other materials.


1. Do not tell the students what materials make up the blocks. 2. Have the students touch each block and describe what they observe. 3. Ask the students which block they think will melt an ice cube the quickest. 4. Place equal sized ice cubes on each block and observe. Have volunteers time how long

it takes for each ice cube to melt. 5. Allow the students to occasionally touch the blocks while melting is occurring. 6. After the ice cube on the metal block melts, let the other ice cube melt for about

another 30 to 60 seconds and then end that part of the demonstration. 7. Dry the blocks. 8. Add a new ice cube to each block. After the ice cube is half melted on the metal block,

pick up the 2 pieces of ice and place them on the opposite block. Make observations and discuss.

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TuesdayTuesdayTuesdayTuesday Look at grow beasts and test tube geology – observing labs set up on Monday


• Make supersaturated borax solution and suspend shaped pipe cleaner

• Observe growth of many crystals the rest of the week Cement pucks – make reinforced pucks – individual student lab


trip outside to gather materials

• Pucks are drop tested on Friday to determine the strongest puck.



Happy/sad balls - demonstration

• Discrepant event using two rubber balls with different amounts of cross-linking

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Borax CrystalsBorax CrystalsBorax CrystalsBorax Crystals OverviewOverviewOverviewOverview:::: Students set up the lab individually but may work in small groups to prepare the solution. Growth is evident by the second day. If some students do not experience any growth the solution was likely not supersaturated. If this happens, the students could make a new solution and still have time for crystal growth by the end of the week. The students may take home their pipe cleaner with crystals in a plastic baggie. MaterialsMaterialsMaterialsMaterials and Equipmentand Equipmentand Equipmentand Equipment::::

• Borax – one box (found in the laundry detergent section of a store) • Pipe cleaners – one or two per student – various colors • Plastic spoons • Large transparent plastic cups • Electric hot water kettle – at least 2 • Glass beakers – 600 mL – at least 4

• Wooden craft sticks – one per student • Tape • Plastic wrap


• Students should wear safety glasses when making solutions • Caution students about using hot water to avoid burns

TeacherTeacherTeacherTeacher Notes/Notes/Notes/Notes/Background/Background/Background/Background/Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:

• Students will each make their own set-up but can work in teams to accomplish the tasks. • Allow the crystals to grow for several days • The students may take the pipe cleaners with crystals home in a sandwich baggy on the

last day.

• If using white pipe cleaners, food coloring may be added to the borax solution to make colored crystals.

• The purpose is to demonstrate how easy it is to grow multiple crystals from a supersaturated solution as the water cools and evaporates.

• Using electric kettles to heat the water is quicker and safer than using beakers and hot plates.

• The students can work in teams of 2 or 3 to make the solution. The ratio of 3 heaping tablespoons of borax to 250 mL of water is given to the students. Different size beakers may be used if you do not have enough of one size. Then students use ratios to determine how much borax and water they need for the number of people in their group.

• Glass beakers should be used to make the borax solution. Allow the solution to cool until the beaker can be comfortably handled. Pouring hot solution into the plastic cups can cause the cups to shrink and deform.

• The students can work on shaping their pipe cleaners while the solution cools. • A hand lens or magnifier is useful for making observations during the activity.

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1. Make a supersaturated borax solution – students may work in pairs or small groups and share the solution.

a. Use a glass beaker to mix borax powder and hot water. b. Add 3 heaping tablespoons of borax powder for each cup of hot water (one cup

= about 250 mL). c. Stir until the borax powder dissolves. d. Allow the solution to cool.

2. Make a shape out of a pipe cleaner that will fit into your plastic cup without touching the sides.

3. Attach the pipe cleaner to a wooden craft stick so that it will suspend into the plastic cup of solution. You may need to use a second pipe cleaner to get the right length.

4. Write your name on your cup with a sharpie. 5. Pour the cooled solution into a plastic cup – fill the cup about 2/3’s full. 6. Suspend pipe cleaner in solution 7. Tape the wooden craft stick to the cup. 8. Loosely cover the cup with plastic wrap. 9. Make daily observations of crystal growth.

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OobleckOobleckOobleckOobleck

OverviewOverviewOverviewOverview:::: Students work individually to make a batch of oobleck. As the instructor identifies students who have made oobleck of the right consistency then they can help other students match it. Once it appears that all students have a “good” batch of oobleck then testing can begin. The testing should be done in a controlled fashion with teacher led directions. The Time Warp video is a good way to wrap up the lab. It is about seven minutes long. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• Small plastic cups • Wood craft sticks • Water • White powder (cornstarch)


• No known safety hazards. Water and/or powder should be wiped up if spilled to prevent slipping on a wet surface (and making a big mess).


• Paper Dixie cups may be used but small plastic cups hold up better. • 5 oz. size cups work very well. • To save time, the instructor may put the corn starch into the cups before class starts. • There is the potential for a mess if the students are not closely monitored. But corn

starch is nontoxic and does not stain clothes. (Starch can be sprayed and ironed on clothes to prevent wrinkling and is used to make gravy.)

• It takes a bit of patience to mix the cornstarch and water. The starch doesn’t fully dissolve; it is more of a suspension. The powder will slowly mix into the water.

• Have the students add water a little at a time to the powder. It is easier to keep adding water than to keep adding powder.

• A “correctly-made” batch of oobleck should move like a fluid (liquid) when slowly stirred. It will be thick and viscous but still flow. When stirred quickly (more shear force applied), the mixture should “lock up” and behave like a solid. Upon sitting still, the mixture will return to its fluid state.

• If the craft stick is slowly pushed down through the mixture, little resistance will be felt and the stick will reach the bottom of the cup. If the craft stick is quickly rammed onto the surface of the mixture it will not be able to penetrate into the mixture which has become rigid due to the added energy (force).

• This activity demonstrates a non-Newtonian material. It does not “obey” the laws of Newtonian physics. Oobleck displays a property known as dilatancy which is the tendency to become more rigid (solid) when it is stirred or subjected to a shear force or pressure. Therefore, oobleck is known as a shear-thickening fluid (STF).

• Make sure that all students have the right consistency of oobleck by having them perform the following tests:

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o Stir slowly – should be able to do this but the mixture will be very thick. o Try to stir quickly – should be unable to do this. o Slowly lower the stick to the bottom of the cup and slowly bring it back out. o Quickly tap the surface of the mixture with the stick – the stick should not

penetrate the surface. o Tap the surface of the oobleck with your index finger – your finger should

bounce off the surface. o Gently rest your index finger on the surface of the oobleck – your finger should

sink into the oobleck. • Cornstarch is a polymer which means it is made up of long molecules. The ends of the

starch molecules have a lot of branching (or “hooks”). When stirred slowly, the molecules can still slide past each other. But when a lot of shear force is applied the molecular branches get caught on each other and the mixture becomes rigid temporarily until the force is removed.

• Additional tests that could be performed on the oobleck include: o Lower the stick to the bottom of the cup, while grasping the cup firmly with one

hand try to quickly pull the stick out of the cup with your other hand. o Set the cup of oobleck on a table and lower the stick to the bottom of the cup.

Quickly pull up on the stick without holding the cup. The cup should lift off of the table. Quickly lower the cup back to the table.

o As a teacher demonstration: pour the oobleck into your hand and roll it into your hand and roll it into a ball. You will have to keep it constantly in motion or it will liquefy. Place the ball onto a hard surface and tap it with a hammer. The force of the hammer should harden the oobleck and cause it to crack and break. Afterwards the pieces will begin to ooze and flow once the force has been removed.

• Do not dispose of the oobleck in the sink as it can harden if not enough water is present. Either let the students take it home in a plastic baggie or place it in a trash can.

• An excellent video to show the students is: Time Warp: Non-Newtonian Fluid http://www.youtube.com/watch?v=S5SGiwS5L6I


1. Fill a plastic cup approximately 1/2 full with white powder (cornstarch). 2. Add 1/3 as much water. 3. Mix the water and powder using a wooden craft stick. The consistency should be like

very thick pancake batter or toothpaste. 4. Follow the teacher’s directions to test the characteristics of the oobleck:

• Stir slowly • Try stirring quickly • Push the stick to the bottom of the cup slowly • Tap the surface of the oobleck quickly • Tap the surface of the oobleck with your index finger

• Let your index finger gently rest on the surface of the oobleck

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WednesdayWednesdayWednesdayWednesday Polymer Theme DayPolymer Theme DayPolymer Theme DayPolymer Theme Day

Look at grow beasts and test tube geology – observing labs set up on Monday


• Make supersaturated borax solution and suspend shaped pipe cleaner • Observe growth of many crystals the rest of the week

Cement pucks – make reinforced pucks – individual student lab


trip outside to gather materials • Pucks are drop tested on Friday to determine the strongest puck.



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Investigating Plastic Properties at Elevated TemperaturesInvestigating Plastic Properties at Elevated TemperaturesInvestigating Plastic Properties at Elevated TemperaturesInvestigating Plastic Properties at Elevated Temperatures (HDPE Jug(HDPE Jug(HDPE Jug(HDPE Jug and Heat Gunand Heat Gunand Heat Gunand Heat Gun DemonstrationDemonstrationDemonstrationDemonstration))))

OverviewOverviewOverviewOverview:::: This is a demonstration to be performed by an instructor. The HDPE jug and the PETE bottle may be passed around by the students after they have cooled. A second part to the demonstration is shrinking the upper half of a PETE bottle using the heat gun. This demonstration works well at the beginning of polymer day as an introduction to polymers and their properties. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• HDPE plastic jug (#2 recycling code) – such as a distilled water, milk or orange juice jug – rinsed and dried

• PETE plastic bottle (#1 recycling code) such as a 16 oz. soda bottle – half full of water • Plastic preform • Heat gun – sold as a paint stripper at Walmart, hardware stores or home improvement

stores

• Extension cord if needed


• Make sure the HDPE jug is dry before starting the demonstration to avoid steam burns when blowing air into the heated jug.


• One method of classifying polymers (plastics) is by their reaction to heat. The two main categories are thermoplastics and thermosets.

• Thermoplastics soften or melt when heated and resolidfy when cooled. These are the primary types of polymers used for recycling (HDPE, PETE, etc.) that display the triangular recycling codes.

• Thermosets are polymers that set permanently into a solid form when made by an exothermic reaction. They cannot be re-softened or melted by heat and therefore are difficult to recycle. They can be shredded and used as fillers in other polymer materials.

• This demonstration uses thermoplastics. A polyurethane thermoset is used in one of the polymer station labs.

• HDPE is high density polyethylene. The jug is translucent because the polymer chains are mostly in an amorphous (random) arrangement with some regions of crystallinity (orderly arrangement).

• The more random the chains become in HDPE the more transparent it will appear.

• As crystallinity increases in HDPE the more opaque it appears. • The first part of the demonstration involves heating one side of the HDPE jug with the

heat gun and observing changes in optical properties. It also demonstrates how heat can be used to change the shape of thermoplastics.

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• Drinking bottles, such as soda bottles or water bottles, can also be used to demonstrate properties of thermoplastics. These bottles are made of polyethylene terephthalate (recycling code #1).

• The second part of the demonstration involves shrinking the upper half of a PETE bottle using the heat gun.

• The PETE bottle was formed by heating a preform and then blow molding to expand the preform to bottle shape. Upon heating above the softening temperature the plastic bottle begins to return to the shape of the original preform – a form of polymer memory.


1. Remove the cap or lid and heat the side of a milk jug, distilled water jug, or Sunny Delight bottle (#2 recycling code plastics) with a heat gun (paint stripper).

2. The polymer chains will start to relax as they gain energy and will lose some of their crystallinity. The heated area will become more transparent and softer (flexible).

3. Allow the jug to cool. As it slowly cools the polymer chains have time to arrange in a more orderly fashion than they were originally (have more crystallinity) and the affected area will now appear more opaque than the rest of the jug.

4. Reheat the jug until the area becomes transparent and flexible again. When it reaches this point, gently blow into the opening of the container. This is an example of blow molding. The polymer will stretch and expand and take on a new shape. This demonstrates the nature of a thermoplastic.

5. As the jug cools, the stretched area will become less transparent as the chains lose mobility and regain some crystallinity.

6. Half fill a used PETE (soda or water) bottle with water. Do NOT put the cap or lid back on.

7. Hold the bottom of the bottle with one hand while heating the top half with the heat gun. The water has a high specific heat capacity and will prevent the bottom half of the bottle from being affected by the heat gun.

8. The top half of the bottle will being to shrink back to the size and shape of the original preform from which it was made. Show the students a preform for comparison. This also demonstrates the nature of a thermoplastic.

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Water Gel CrystalsWater Gel CrystalsWater Gel CrystalsWater Gel Crystals

OverviewOverviewOverviewOverview:::: This is an individual student lab. The students make initial observations and measurements on the first day (Wednesday). Final observations are made on Friday. The students may take home their hydrated crystals in a plastic baggie. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• Water gel crystals (sodium polyacrylamide) – also known as ghost crystals

• Small plastic cups

• Sharpies to label the cups • Plastic pitchers of water • Electronic balance


• Students should not ingest the water gel crystals. Wash hands at completion of the lab. Teacher Notes/Teacher Notes/Teacher Notes/Teacher Notes/Background/Background/Background/Background/Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:

• The lab is set-up on one day and the final results are observed one or two days later. • Students will need a method of recording data – tablets, iPads, wall charts or lab

notebooks are suggestions. • Students will need to choose the largest crystals in the container so the mass will register

on the balance. It will save time during class if the teacher sorts out enough large crystals for the students ahead of time.

• Tap water or distilled water may be used for the lab. • Water gel crystals (sodium polyacrylamide) are a very hygroscopic polymer. They will

absorb many, many times their weight in water.

• The hydrated crystal will basically have the same index of refraction as water and therefore will appear to be invisible in the water. This is why they have the nickname “ghost crystals”.

• When students check their crystal after hydrating for 24 to 48 hours, they often think that it has disappeared somehow. The students make comments such as “it dissolved” or “someone took it”.

• The students can either gently “search” the contents of the cup with their finger or carefully pour the water out of the cup to discover the hydrated gel.

• To avoid getting pieces of the gel caught in the drain, have the students pour water from their cup into a plastic pitcher or bowl.

• The students can either take their hydrated crystal home in a plastic baggie or disposed of it in the trash can.

• Food coloring can be used in the water to make colored gels. • Sodium polyacrylamide also comes in spheres of various sizes. • The gels will dry back out and return to their original shape and size over time. The

dehydrated crystals will be somewhat discolored if tap water was used for the lab.

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• Water gel crystals have many practical uses: water retention in potted plant containers, neck coolers, landscaping and agriculture in dry climates to help retain soil water, environmental spill cleanup, hydroponics (growing plants without soil), provide a clean water source for pet insects and reptiles, etc. Sodium polyacrylamide is also used to make soft contact lenses.


1. Choose a water gel crystal. 2. Use the electronic balance to find the mass of your crystal. 3. Record the mass of the crystal and draw it actual size (or take a picture of it). 4. Describe the water gel crystal: color, shape, hardness, texture, etc. 5. Label a plastic cup with your name and place the water gel crystal in the cup. 6. Almost fill the cup with water. 7. Predict what you think will happen to the crystal. 8. Let the cup and crystal sit for 24 to 48 hours. 9. After 24 to 48 hours, pour the water from the cup and catch the crystal in your hand. 10. Record the mass of the hydrated crystal and draw it actual size (or take a picture of it). 11. Describe the hydrated crystal: color, shape, hardness, texture, etc. 12. Brainstorm practical uses of this material.

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Gak and SlimeGak and SlimeGak and SlimeGak and Slime

OverviewOverviewOverviewOverview:::: This is an individual student station lab. There will be 4 to 5 students working at this station at a time. Four different polymer station labs are set up at the same time. Each rotation takes about 20 to 25 minutes. Each station will need an instructor/adult leader. The teacher/leader demonstrates the effect of borax solution on a solution of Elmer’s glue and water, this forms a substance known as gak. Then the students make colored slime out of polyvinyl alcohol solution and differing amounts of borax solution. Students investigate and compare the properties of each batch of slime. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment: Teacher Demonstration:

• 100 mL of water • 100 mL of Elmer’s glue • 4% borax solution • Plastic baggie

Student lab:

• 4% polyvinyl alcohol (PVA) solution - 50 mL per student • 4% sodium borate solution (borax) • 5 oz. plastic cup • wooden craft stick • graduated cylinder • food coloring • plastic baggie • funnel (optional)


• Safety glasses/goggles should be worn.

• The borax and the PVA will burn the eyes. Hands should be washed at the end of the lab.


• The teacher should first demonstrate the making of gak using an Elmer’s glue/water solution and borax solution.

• Elmer’s glue contains polymer chains (polyvinyl acetate) that are free to slip and slide around each other.

• The borax solution acts as a cross-linker forming hydrogen bonds with the polymer chains in the glue. This forms a putty type of material often called gak.

• 300 mL of 4% borax solution should be enough for the teacher demonstration and student lab. Mass out 12 grams of borax powder in a beaker. Add 288 mL of boiling water and stir until dissolved.

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• After the teacher demonstration the students makes slime using polyvinyl alcohol (PVA) solution and borax solution. The students add different amounts of the borax solution to their PVA solution. Cross-linking occurs and a slime or gel is formed. The slimes will have different viscosities/consistencies based on the amount of cross-linking that occurs.

• Students compare/contrast the properties of the different slimes made by the group. The students can then add more borax solution or PVA solution to their baggie to achieve a slime with the most desirable properties.

• An additional test that could be performed is to time how long it takes for each batch of slime to flow through a funnel – a comparison of their viscosity.

• The PVA can be purchased as a solution or as a powder. It is much more economical to make your own solution using the powder.

• A beaker may be used to make the PVA solution. Add 4 grams of PVA powder to 96 mL of tap water and stir. The PVA will suspend briefly but will not dissolve until heated. To make larger amounts just multiply the amount of ingredients by the appropriate factor. Cover the beaker with microwaveable plastic wrap and stir between heating segments. Microwave for 2 - 3 minutes at a time depending on the amount of solution. Heat to 80°C. Microwave an additional minute at a time if needed. The prepared solution should be clear and somewhat viscous. The PVA solution will often still look slightly cloudy at this point but it will clear upon sitting. Do not heat above 80°C. The solution stores well in the refrigerator until needed.

• Each student will need 50 mL of PVA solution, so a class with 20 students would need a liter of PVA solution. It is recommended that an extra 100 - 200 mL of solution be made to allow for spills, etc.

• Store the PVA in water bottles with sport tops. This makes it much easier and less messy for the students to pour the PVA into their cups. It is recommended that you make 4 bottles and add food coloring ahead of time as students tend to add too much food coloring which can lead to stains.

• It should be emphasized that the students did not make polymer chains. The polymer chains are dissolved in the water in the PVA solution; they were already there. The sodium borate (borax) just “ties” the polymer chains together making it a more cohesive mass.

• Polymer chains are formed by covalent bonds which are strong bonds. In making slime, individual polymer chains are “hooked” together by weak hydrogen bonds. It is evident that this cross-linking is weak because of the ease with which the slime pulls apart. It is sort of like “tying” together strong strands of string with limp strands of cooked spaghetti. Even though this cross-linking is weak, it does alter the properties of the polymer.

• An observation that the students can make is how cool the slime feels. As the slime is stretched it has more surface area exposed to air and the evaporation rate of the water is increased. What they are feeling is the effect of evaporative cooling.

Procedure:Procedure:Procedure:Procedure: Teacher Demonstration:Teacher Demonstration:Teacher Demonstration:Teacher Demonstration:

1. Thoroughly mix equal amounts of glue and water in a plastic baggie. 2. Slowly add small quantities of borax solution to the baggie. 3. Note when the gak sticks to itself and not to the side of the bag.

Student Lab:Student Lab:Student Lab:Student Lab:

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Assign each student one of the following “recipes”: StudentStudentStudentStudent PVAPVAPVAPVA BoraxBoraxBoraxBorax solutionsolutionsolutionsolution 1 50 mL 1 mL 2 50 mL 2 mL 3 50 mL 4 mL 4 50 mL 6 mL 5 50 mL 10 mL If there are only 4 students in the group eliminate the 1 mL recipe.

1. Add PVA to plastic cup. 2. Add borax solution - stirring quickly making sure to scrape the sides and bottom using

the wooden craft stick. 3. Pour entire contents of the cup into a plastic baggie and gently knead. 4. Compare properties of the different slimes while in the baggie, some suggestions

include: a. Check flow by tilting bag side to side. b. Pinch the slime to feel stiffness.

5. Determine which slime has the best characteristics. 6. Add borax solution or PVA solution to make your slime the best consistency. 7. Take slime out of baggie and “investigate” properties.

• bouncing • stretching slowly • stretching quickly • letting it flow from one hand to another • flow rate through a wide mouth funnel • etc......

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Thermoset Polymer Thermoset Polymer Thermoset Polymer Thermoset Polymer –––– Eurocast in Silicone MoldsEurocast in Silicone MoldsEurocast in Silicone MoldsEurocast in Silicone Molds OverviewOverviewOverviewOverview:::: This is an individual student station lab. There will be 4 to 5 students working at this station at a time. Four different polymer station labs are set up at the same time. Each station will need an instructor/adult leader. Each rotation takes about 20 to 25 minutes. Instructors premeasure the two resins. Students add pigment, mix the resins together and pour it into a silicone mold. The finished polymer piece is used the next day to make a mold to pour molten tin into. Students get to take home identical polymer and metal pieces made by casting. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• Eurocast resins - Parts A and B • Paper measuring cups • Paper Mixing cups • Small silicone ice molds • Plastisol pigments • Wooden craft sticks (for stirring) • Fantastik cleaner • Plastic sheeting for covering tables


• Safety glasses/goggles should be worn.

• Plastic disposable gloves should be worn. • Fantastik multipurpose cleaner and paper towels should be on hand to clean any spills.

Teacher Notes/Teacher Notes/Teacher Notes/Teacher Notes/Background/Background/Background/Background/Suggestions/Helpful Suggestions/Helpful Suggestions/Helpful Suggestions/Helpful Hints:Hints:Hints:Hints:

• Casting is a type of manufacturing process. It can be used for various materials such as metals, polymers and ceramics. It involves pouring a liquid into a mold and allowing it to solidify. The solidification can occur by various means such as freezing, exothermic reaction, drying, etc. depending on the type of material.

• This lab involves polymer casting. The piece made will be used as a model to make a mold to cast metal in the next day.

• Eurocast is a thermoset polyurethane. It is a 2 part resin system that forms a solid polymer after an exothermic reaction occurs between the 2 parts.

• Thermoset polymers are formed into hard solids during a chemical reaction involving heat. These polymers are permanently “set” and cannot be melted or reheated for recycling.

• Most of the materials come from IASCO-TESCO – an industrial arts supply company. http://iasco-tesco.com/catalog/

plastisol pigment - blue opaque OP-2

plastisol pigment - green opaque OP-5 plastisol pigment - red opaque OP-6

plastisol pigment - yellow opaque OP-11

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mixing cups - coated - 7 oz. - 100/pkg BL-7

3 oz. measuring cups - sleeve of 100 2503

Almond Eurocast Quart Kit AU-32

• Small silicone ice molds can be purchased from discount kitchen supply stores. A variety of shapes are recommended such as footballs, cars, stars, hearts, dogs, etc.

• Cover tables with plastic sheeting and clean up any spills immediately with Fantastik cleaner.

• The instructor should measure out the two resins into individual paper measuring cups for each student. This can be done ahead of time. The two resins are measured out in a 1:1 ratio. To determine the amount needed, find the volume of the largest mold cavity by filling with water and pouring into a graduated cylinder. Divide this volume by half and pour that amount of each resin. If the students are allowed to make more than one piece adjust the amount of resin accordingly.

• The pigment is too thick to use a pipette. The students use a wooden craft stick to add pigment to each cup of resin. Do not reuse a stick that has touched the resin. Use a separate craft stick to add pigment to cup A and cup B. Students can add a different pigment to each cup to make a blended color – for example yellow in one cup and red in the second cup to make orange.

• The color is vivid in the liquid resin. The color becomes muted as the Eurocast hardens into a solid. Hardened Eurocast with no pigment added is almond colored. Therefore a true red is not obtainable. Using a small amount of red pigment will result in a pink solid and using larger amounts of red pigment will result in a fuchsia solid.

• Timing is crucial. Once the two resins are poured into the same cup, thorough stirring/mixing must occur for 30 seconds and then poured into the mold(s) before the polymer begins to set up.

• The students should touch the side of the mold when the Eurocast begins to harden to feel the heat given off by the exothermic reaction.

• The pieces can be popped out of the mold as soon as they are cool enough to handle. • Each student will need one polymer piece to use as a pattern for metal casting the next

day. Procedure:Procedure:Procedure:Procedure:

1. Choose which mold(s) you want to use. 2. Each student needs two cups of resin – one with Part A and one with Part B. 3. Add pigment to each cup using a wooden craft stick. Be sure to use a separate stick for

cup of resin. 4. Pour both resins into a larger cup and stir for 30 seconds scarping the

sides and bottom to mix well. 5. Fill molds to edge but do not let run over. 6. Let sit for 10 minutes or until cool enough to handle and remove from

the mold. 7. Choose a piece to use as a pattern to make a metal casting.

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SSSShrinking Plasticshrinking Plasticshrinking Plasticshrinking Plastics

OverviewOverviewOverviewOverview:::: This is an individual student station lab. There will be 4 to 5 students working at this station at a time. Four different polymer station labs are set up at the same time. Each rotation takes about 20 to 25 minutes. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• scissors • rulers • permanent markers • polystyrene - PS - (recycling code #6) plastic: salad trays, bakery boxes, etc. • tray covered with aluminum foil • spatula • toaster oven • pot holder • hole punch • two ceramic tiles (optional)


• Students should use caution when using the toaster oven to prevent burns. Teacher Notes/Teacher Notes/Teacher Notes/Teacher Notes/Background/Background/Background/Background/Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:

• The plastic used in this activity (polystyrene) is easy to work with when heated. While hot, polystyrene can be stretched into any shape required. Normally, the polymer chains in a piece of polystyrene are jumbled together in an almost random way (think of wet spaghetti noodles dumped on a plate). When heated, the strands can be stretched into a more ordered pattern and “frozen” in place. If the polystyrene is reheated, it returns to its original shape (a type of “memory polymer”.)

• A plastic that softens upon heating and can be reshaped is known as a thermoplastic. Thermoplastics can be melted or softened to make new products and thus are recyclable. They include polyethylene, polypropylene, polyvinyl chloride (PVC), and polystyrene (PS). Products and packaging made from one of these thermoplastics are stamped with the recycling symbol – a triangle of arrows with a number (1 – 7) inside.

• Polystyrene (PS) plastic sheets can be purchased at a hobby or craft store. Used plastic food containers with recycling code #6 can also be collected and washed – these possibly include salad trays, bakery boxes, etc.

• Creative-Coldsnow is an art supply company that sells 8 1/2” by 11” sheets of polystyrene. http://www.creativecoldsnow.com/search.htm?searchterm=Grafix+shrink+film&searchmode=phrase&s_category=0&DoSearch=Show+Matches&numresults=100&viewfrom=1&step=2 – a package of 50 sheets is less than $25. Cut the sheets into fourths to fit into the toaster oven.

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• The accuracy of the temperature setting varies on toaster ovens. Start with the toaster oven preheated to 275º F. Adjust the setting up or down as needed.

• It should take about one minute for the plastic to shrink. If it is taking much longer than that, adjust the temperature up a little at a time. If the plastic shrinks very quickly and becomes tacky or starts to melt, lower the temperature. Do some practice trials before class to find the correct setting for your toaster oven.

• Toaster ovens cycle on and off like a furnace. When the oven cycles off the shrinking process will pause; shrinking will resume when the oven cycles back on. Inform the students that they are not to adjust the setting on the toaster oven.

• If the students pull the plastic out of the oven too soon and it has not finished shrinking and flattening, it is possible to put it back into the oven to finish the process.

• Sometimes the plastic curls up and sticks to itself while shrinking. Usually it will uncurl and flatten on its own. If it doesn’t come undone, it is possible to use two fork to pull the plastic apart and then let it continue to shrink.

• The plastic usually shrinks 80 to 90% in area. The plastic is hard and brittle after it shrinks and cools. Therefore, if a hole is desired, it must be punched into the plastic before shrinking.

Procedure:Procedure:Procedure:Procedure: 1. Create a design on your piece of polystyr1. Create a design on your piece of polystyr1. Create a design on your piece of polystyr1. Create a design on your piece of polystyrene plastic.ene plastic.ene plastic.ene plastic.

• Use permanent markers to write and draw your chosen design. • Use scissors to get rid of sharp corners and shape the plastic. • Use the hole punch to make 3 overlapping holes in from an edge if you want to hang it

from a string or chain. 2. 2. 2. 2. Shrink the plasticShrink the plasticShrink the plasticShrink the plastic

• Preheat the oven to approximately 275° F. • Place the piece of polystyrene on an aluminum foil covered tray and place it in the oven. • Watch the plastic shrink – it should take about one minute. • It will sometimes curl up as it heats. It will usually uncurl on its own given time. • Once it has uncurled, it can be removed from the oven. • Watch it carefully. Sometimes it will curl up and “stick” to itself. • You can usually “undo” it by manipulating it with forks.

3. Flatten and cool the 3. Flatten and cool the 3. Flatten and cool the 3. Flatten and cool the plasticplasticplasticplastic

• Remove the plastic piece from the oven with the spatula. • Press the piece between two ceramic tiles to flatten and cool.

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Polymer PowdersPolymer PowdersPolymer PowdersPolymer Powders

OverviewOverviewOverviewOverview:::: This is an individual student station lab. There will be 4 to 5 students working at this station at a time. Four different polymer station labs are set up at the same time. Each station will need an instructor/adult leader. Each rotation takes about 20 to 25 minutes. This lab is designed to allow the students to experiment/explore with the different powders and water. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• Water lock powder (sodium polyacrylate) • Instant snow powder (highly cross-linked sodium polyacrylate)

• High density polyethylene (HDPD) powder • Measuring spoons or small plastic spoons • Wax paper • Plastic petri dishes • Disposable pipettes (or eye droppers) • Pitchers of water • Plastic cups • Food coloring


• Students should wear safety glasses when experimenting with the powders. • Students should wash their hands after experimenting with the powders.

Teacher Teacher Teacher Teacher Notes/Notes/Notes/Notes/Background/Background/Background/Background/Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:

• Water lock (sodium polyacrylate) and instant snow are very hydrophilic. They absorb many times their mass in water and are called superabsorbent.

• Water lock is used in disposable diapers, hair gels, meat packaging (the thin sheet under the meat absorbs blood), humidity control in walls, and as a fire retardant.

• An excellent five minute to show the students is: Barricade Fire Gel on the DIY Network -http://www.youtube.com/watch?v=Ub1OfjDYiUE

• Instant snow is used as fake snow for TV shows and movies as well as an artificial snow base for skiers. It is also used as a blood absorbent and industrial spill containment.

• The activity works with both distilled water and tap water. Water lock will absorb about 800x its mass in distilled water and 300x its mass in tap water.

• Sodium polyacrylate is a polymer. Instant snow is a highly cross-linked polymer that forms small granules. Water lock is a very fine powder while instant snow feels more granular.

• When water is added to water lock, it forms a gel that feels moist and has approximately the same volume as the water that was added.

• When water is added to instant snow, water enters the small granules and hydrate the polymer from the inside. This causes it to expand and increase in volume. It feels drier than water lock and looks like fluffy snow. As more and more water is added the

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granules begin to feel wet on the outside and the granules stick together to form a slush.

• An extension to this activity can be to have the students determine the ratio of water to instant snow that makes the best fake snow. They will have to measure the amounts used and determine as a group what constitutes a “perfect” snow.

• High density polyethylene (HDPE) powder is very hydrophobic polymer. It repels water.

• HDPE looks very similar to the other two powders but behaves very differently. • HDPE is the polymer in containers with the #2 recycling code. It is used to make milk

jugs, detergent bottles, orange juice jugs, gallon jugs for distilled water, etc. • Plastic petri dishes or wax paper can be used for the students to explore and experiment

with the powders. • It is helpful to have small labeled plastic cups for the three powders for the students to

use. They can be restocked by the instructor while the groups rotate from one station to the next.

• Have measuring spoons or small plastic spoons for the students to put small amounts of each powder in their petri dish or on wax paper. Or the instructor can spoon it out for the students to have control over how much is used.

• To clean up, the students can wipe the powders and water into a trash can with a paper towel if using a petri dish.

• In addition to the students individually exploring the properties of the powders with water, there are two instructor demonstrations.

o Have a transparent plastic cup (punch style cup works great) about three-fourths full of water with about one-quarter inch of HDPE powder layered on top available. Slowly lower your finger into the cup of water. The HDPE powder will protect your finger and keep the water away. Your finger will be dry when you remove it from the cup. Students will want to try this themselves. It is a good idea to have one cup ready for each group rotation.

o Add food coloring to a pitcher of water. Place a small amount of water lock in one transparent cup and a small amount of instant snow to another cup. Add colored water to each cup. The color of the hydrated water lock will be vivid and bright while the color of the hydrated instant snow will be muted. The water attaches along the outside of the polymer chain in water lock. The water enters the instant snow clusters and expands them.


1. Add a small amount (about half a teaspoon) of water lock near one edge of your petri dish (or onto wax paper).

2. Slowly add drops of water with a disposable pipette or eyedropper. Make observations. 3. Repeat steps #1 and 2 with instant snow and with HDPE powder. 4. Brainstorm possible uses of each type of polymer powder based on their properties. 5. If time allows, experiment with combinations of the different powders.

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ThursdayThursdayThursdayThursday MetalMetalMetalMetal Theme DayTheme DayTheme DayTheme Day



Rusty spheres and aluminum foil / Thermite in your hand - demonstration

• Two rusty iron spheres and aluminum foil are used to demonstrate the thermite reaction • A single replacement reaction occurs between the iron oxide and aluminum when struck with enough force – sparks and noise are produced!

Aluminum can liner - demonstration

• The aluminum is eaten off of a sanded pop can when placed in hydrochloric acid – single replacement reaction

• The polymer liner is exposed

• Shows that food cans and drink cans need protection from corrosion Steel wool corrosion – small group lab

• Students place steel wool in different environments (solutions) and observe the rate of corrosion

• Shows the factors that need to be present for corrosion to occur Metal sand casting – station lab – individual

• Students use the Eurocast piece they made on Wednesday to make a mold out of moon sand

• The teacher/leader pours molten tin into the mold • Students clean their cooled metal piece and take home both the polymer and metal pieces they made

Fruit batteries – station lab - group

• Students use oranges, metal strips and a voltmeter to determine which combination gives them the most voltage

• This is a way of determining the activity series of metals which should parallel the results they get during the Activity Series lab

Activity series – station lab - group

• Students look for signs of chemical reaction between copper sulfate solution and six different metals

• Students as a group rank the metals from most to least reactive – the results should parallel the outcome of the Fruit Batteries lab

Brassing a penny – station lab - individual

• Students zinc-plate a clean penny and then use a hot plate to make brass on the surface by solid state diffusion

• The students also explore The City of Materials website which includes a virtual lab and simulation of the experiment

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Thermite in Your HandThermite in Your HandThermite in Your HandThermite in Your Hand DemonstrationDemonstrationDemonstrationDemonstration

OverviewOverviewOverviewOverview:::: This is a teacher demonstration. The spheres will need to be rusted ahead of time. The demonstration can be performed before or after the metal stations. A connection can be made to the Fruit Battery lab and the Developing the Activity Series lab. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• 2 Rusty iron spheres • Aluminum foil


• Safety glasses should be worn by the demonstrator. • Be careful to keep a tight grip on the spheres so they don’t fall on your foot. • Be sure to keep your hands on the sides to avoid smashing your fingers.


• This lab is a quick, easy and safe version of the traditional thermite lab.

• Strike the balls together at very rusted spots. • A glancing blow is required to generate enough friction and heat to initiate the reaction

between the iron oxide and aluminum. • A single replacement reaction occurs between the iron oxide (rust) and aluminum when

struck with enough force. The reaction is very exothermic - sparks and noise are produced!

• Aluminum is more reactive than iron so it will replace the iron in iron oxide to form aluminum oxide and pure iron.

• Al + Fe203 --> Al2O3 + Fe + heat • A quick way to rust the iron spheres is to submerge the spheres in a plastic cup with 3%

hydrogen peroxide and salt. A vigorous reaction will soon begin to occur. This is quicker than using just salt water because of the extra oxygen released by the breakdown of the hydrogen peroxide. After about an hour, pour off the solution and periodically spray the spheres with hydrogen peroxide. Rotate the spheres occasionally. After several hours let the spheres dry before performing the demonstration.

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Procedure:Procedure:Procedure:Procedure: 1. Wrap one of the rusted iron spheres with aluminum foil. If the spheres are small than 2”

in diameter, it can be helpful to use a larger sheet of foil to wrap the sphere and twist the excess foil into a “handle” to hold while striking the spheres together.

2. Hold the aluminum foil-wrapped sphere in your nondominant hand and the non-

wrapped sphere in your dominant hand. 3. Using a glancing blow, strike the two spheres together. 4. White sparks and a loud crack should be produced as the spheres strike and slide past

each other. 5. To repeat the demonstration, rotate the rusted iron sphere to strike a fresh surface of

iron oxide.

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Aluminum Can LinerAluminum Can LinerAluminum Can LinerAluminum Can Liner DemonstrationDemonstrationDemonstrationDemonstration

OverviewOverviewOverviewOverview:::: This is a teacher demonstration. The can will need to be prepared before class. The demonstration illustrates a practical application of the activity series of metals. It is best to show it after doing the metal station labs. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• Aluminum pop can • 600 mL beaker • Scotch brite pad • 3M HCl • Masking tape • Thick gauge copper wire or glass stirring rod


• Wear appropriate lab safety gear such as safety glasses and lab aprons and consult specific MSDS.

• The tab must be poppedtab must be poppedtab must be poppedtab must be popped before putting the can in the acid. The exothermic reaction generates enough heat to create enough pressure inside the can to cause it to rupture and explode.

Teacher Notes/Teacher Notes/Teacher Notes/Teacher Notes/Background/Background/Background/Background/Suggestions/HelpfulSuggestions/HelpfulSuggestions/HelpfulSuggestions/Helpful Hints:Hints:Hints:Hints:

• Aluminum is a reactive metal. Normally the surface oxides and the oxidation adheres tightly to the surface of the aluminum and prevents it from further corrosion. If the pH is below 3 or above 8 or chloride ions are present, then the oxidation coating does not adhere to the surface and corrosion continues to occur at a quick rate.

• Soda contains acid and therefore the aluminum can requires a polymer lining on the inside of the can to prevent it from corroding and leaking. The paint on the outside of the can is also a polymer that provides protection.

• The polymer liner is spray-coated onto the inside of the can during production. It is to protect the aluminum from the phosphoric acid that pop contains.

• The chemical reaction that removes the aluminum by using HCl is a simple single-replacement reaction:

o 6HCl + 2Al -----� 3H2 + 2AlCl3

• Use safety precautions when using chemicals. Using HCl will produce hydrogen gas as a by-product and is an exothermic reaction.

• Adding too much HCl at a time may cause the polymer liner to melt from the heat generated or rip due to vigorous bubbling

• Masking tape can be used to make a design on the can, such as stripes or windows, before sanding the paint off the outside of the can.

• If windows are sanded instead of the entire can, then the can does not have to be suspended by a copper wire or glass rod.

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• Steel wool or sandpaper can be used to remove the paint from the can but a scotch brite pad (from the paint department) works quickly and easily.

• Once all the acid has been thoroughly rinsed from the can, the polymer liner may be gently touched. Food coloring may also be added to the water inside the can to make it more visible.


1. Remove the paint from an unopened pop can.

• Use a scotch brite pad (found in the paint department at Walmart or Lowe’s). • Using an unopened pop can makes it much easier to remove the paint without

denting the can and causing a leak. 2. Pop the topPop the topPop the topPop the top and empty the soda out of the can and rinse. 3. Poke 2 holes on opposite sides of the can near the top. (This step can be omitted if

using sanded windows instead of the entire can.) 4. Run a copper wire through the holes to suspend the can in a beaker OR use a stirring

rod to suspend the can by the tab. 5. Fill the can with cold water (the reaction to remove the aluminum is exothermic) 6. Suspend the can in a 600 mL beaker. 7. Gradually add 3M HCl to the beaker.

• Add between a half inch and an inch at a time. • Once the reaction stops, add another 1/2 to 1” of acid. • Concentrated copper II chloride or copper II sulfate (with NaCl added) solution

may be used instead of acid 8. Once the desired amount of polymer liner is exposed, remove the can from the acid. 9. Gently rinse the outside of the can with running water. 10. Place the can (with supports) in a beaker of water.

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Steel Wool CorrosionSteel Wool CorrosionSteel Wool CorrosionSteel Wool Corrosion

OverviewOverviewOverviewOverview:::: Students work in groups of 4 or 5. Steel wool (iron-based alloy) is exposed to different environments (solutions) and the rate of corrosion is observed. Four of the solutions are prescribed in the procedure. A fifth solution may be chosen by the group. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• Steel wool • Small plastic cups (5 per group) • 3% hydrogen peroxide • Non-iodized table salt • Pitchers of water • Graduated cylinder • Salt • Additional solutes


• Safety glasses/goggles should be worn. • Hands should be washed at the end of the lab.


• The corrosion of metals is the result of a chemical reaction called oxidation. When exposed to oxygen, iron will rust or oxidize. The surrounding environment affects the rate at which iron or steel corrodes. Factors such as the humidity, presence of salts, amount of oxygen, etc. play a role in how quickly iron will rust.

• Many man-made objects function in areas where the water they are exposed to contains more oxygen than in other areas. Some examples are: steel pilings supporting a bridge over water; a pier at the beach; offshore oil platforms and offshore windmills.

• Use scissors to cut the steel wool into equal sized pieces about 1” in diameter. Pulling on the steel wool can cause metal splinters. It is recommended that the teacher cut the steel wool prior to class and have it ready for the students to use.

• Have extra solutes available for the groups to use in their 5th trial (cup). Suggestions include: sugar, borax, vinegar, etc.

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• Expected results: The steel wool in cup #4 with hydrogen peroxide and salt rusts very rapidly. Cups #1, 2 and 3 show very little evidence of reaction. The cups may be left sitting until the next day. After 24 hours, small amounts of corrosion may be visible. The results of cup #5 will depend on the solute(s) used by the groups.

• Four “ingredients” are necessary for corrosion to occur. They are represented by the

acronym “ACME”: anode, cathode, metallic pathway and electrolyte. All 4 must be present for oxidation to occur. In this lab, the steel wool is the anode, cathode and metallic pathway. The salt is the electrolyte.

• Cup #4 with hydrogen peroxide and salt has both an electrolyte (the salt) and a large supply of oxygen (from the breakdown of hydrogen peroxide) that allows the steel wool to quickly rust. Cups #1 and 3 do not have the electrolyte – the salt. Cup #2 has the salt, but not the source of extra oxygen.

• Metal corrodes much quicker at the ocean’s surface than deep in the ocean. There is not as much oxygen at lower depths and it is often much colder. Wave action incorporates a lot of oxygen into the water at the surface.


1. Label 5 plastic cups 1 through 5. 2. Add the following ingredients to each cup and stir to mix:

Cup #1 – 50 mL of water Cup #2 – 50 mL of water and ½ tablespoon of salt Cup #3 – 25 mL of water and 25 mL of hydrogen peroxide Cup #4 – 25 mL of water, 25 mL of hydrogen peroxide and ½ tablespoon of salt Cup #5 – 50 mL of a solution decided upon by the group and approved by the teacher

3. Place one piece of steel wool in each beaker. Use a plastic spoon to submerge the steel wool.

4. Make initial observations. 5. Let sit for 24 hours and make final observations.

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Metal Sand CastingMetal Sand CastingMetal Sand CastingMetal Sand Casting OverviewOverviewOverviewOverview:::: This is an individual station lab. Students will be in groups of 4 or 5. Four different metal station labs are set up at the same time. Each rotation takes about 20 to 25 minutes. Each station will need an instructor/adult leader. Students make a sand mold using the polyurethane polymer piece they made on Polymer Day. The instructor melts and pours in the molten metal. The students watch the metal solidify then remove and clean it after it cools. Students will take home identical polymer and metal pieces made by casting. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• Shape It! Sand (formerly known as Moon Sand) • Polyurethane plastic piece made on Polymer Day • Small metal containers such as small loaf pans • Tin or other low melt temp metal such as pewter • Hot pot II melter • Ceramic tiles – 12” x 12” or bigger to cover the table top (at

least 4) • Leather gloves such as welding gloves • Needle-nose pliers • Small wire brush for cleaning sand off of metal castings • Plastic or metal bowls with water to cool and rinse metal casting • Heavy duty extension cord

Safety:Safety:Safety:Safety: • Students should wear safety glasses. • Students should be aware of hot surfaces and use caution • Never allow liquid metal to contact water – in the mold or in the hot pot. Make sure the

mold has only dry sand in it. • Hot metal and cold metal are the same color. Wear leather gloves when touching any

metal that may be hot. Consider all metal as hot until proven to be at room temperature.


• Casting is a type of manufacturing process. It can be used for various materials such as metals, polymers and ceramics. It involves pouring a liquid into a mold and allowing it to solidify. The solidification can occur by various means such as freezing, exothermic reaction, drying, etc. depending on the type of material.

• This lab involves metal sand casting. The polyurethane piece made on Polymer Day is used as a model/pattern to make a mold (depression) in the sand which the metal will be cast into.

• The students make the sand mold. The instructor melts the metal and pours it into the mold.

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• Shape It! Sand can be purchased from toy stores or the toy section of discount stores. An economical source is Fat Brain Toys – five pounds for $18.95. Five pounds will be enough. Shape It! Sand was formerly called moon sand. https://www.fatbraintoys.com/toy_companies/waba_fun_llc/shape_it_sand_5_lb.cfm

• The Hot Pot 2 Melter is available from IASCO-TESCO – an industrial arts supply company or from stores such as Bass Pro or Cabela’s.

• Tin or pewter is available from Metalshipper at http://www.metalshipper.com/ and they do accept purchase orders. Order metal in small chunks such as 1” pieces so they will fit in the Hot Pot. Five pounds of metal should be enough.

• Small metal pans such as miniature loaf pans, etc. are excellent for holding the sand. • Make sure that all surfaces that will come in contact with molten metal are completely

dry. If molten metal is poured onto water the water will turn into steam and expand and throw molten metal upward and sideways.


1. Place Shape It! Sand in a suitable size heat resistant container. 2. Push the plastic model into the sand to form an indentation. 3. Pack sand around the plastic model. 4. Remove the plastic model carefully so as not to disturb the

packed sand. 5. Clean any sand that may have fallen into the mold. 6. The teacher will place tin into the preheated Hot Pot 2 melter. 7. Observe the melting process. 8. Place your mold onto the pouring surface – make sure it is dry and heat-resistant. 9. Once the metal is completely melted, the teacher will fill your mold with molten metal. 10. Observe metal as it freezes. 11. Once the metal has completely solidified, move the mold to the side and allow to cool

for 5 – 10 minutes. 12. Demold the metal piece. Remember the sand and metal will still be hot! 13. Cool the metal object in a bowl of water and use a wire brush to clean any remaining

sand. 14. Set the sand aside to cool before reusing to make another mold. 15. File or sand off any sharp or dangerous points or defects.

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Fruit BatteryFruit BatteryFruit BatteryFruit Battery

OverviewOverviewOverviewOverview:::: This is a group station lab. Students will be in groups of 4 or 5. Four different metal station labs are set up at the same time. Each rotation takes about 20 to 25 minutes. Each station will need an instructor/adult leader. Students work as a team to discover which combination of metals will produce the highest voltage using fruit as the electrolyte to make a battery.

Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• Oranges – 4 or 5 • Metal strips • Extra magnesium strips • Extra copper strips • Alligator cords (electrical wires with alligator clips on each end) - 5 • Voltmeter (multimeter) • LED lights (optional)


• Safety glasses/goggles should be worn. • Hands should be washed at the end of the lab.


• Batteries work on the principle of corrosion. All batteries provide their voltage and current by the corrosion of the more easily corrodible (most reactive) of two metals in a couple.

• The results of this lab should mirror the results of the Developing the Activity Series lab. • Flinn Scientific sells a package of metal strips called the “Metal Electrode set” – metals

included are: aluminum, brass, copper, iron, lead, and zinc. OR use the same metals that are used in the Developing the Activity Series Lab – cut the strips into 2” pieces for this lab.

• Instructions dealing with voltmeter (VOM) operation and obtaining proper readings are addressed on the following website: http://www.bcae1.com/vomillia.htm. Note that Electrons flow (-) to (+). Attach black or negative to the MOST reactive metal to get a (+)

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reading on the voltmeter. Use 200mV or 2 Volt scale. Always use the scale that gives the highest meter reading without going beyond the limits of that setting.

• A transfer of electrons takes place between the metal strips and the acid. The more reactive metal is oxidized (gives up electrons) at the anode and the copper is reduced (receives electrons) at the cathode. Because the two metals react differently, the electrons are pushed harder in one direction than the other, which creates the current.

• The table below shows sample data taken from voltmeter recordings of various combinations of metals.

Metal #1Metal #1Metal #1Metal #1 Metal #2Metal #2Metal #2Metal #2 FruitFruitFruitFruit VoltageVoltageVoltageVoltage CopperCopperCopperCopper MagnesiumMagnesiumMagnesiumMagnesium OrangeOrangeOrangeOrange 1.8001.8001.8001.800 CopperCopperCopperCopper AluminumAluminumAluminumAluminum OrangeOrangeOrangeOrange .920.920.920.920

CopperCopperCopperCopper ZincZincZincZinc OrangeOrangeOrangeOrange .820.820.820.820 CopperCopperCopperCopper IronIronIronIron OrangeOrangeOrangeOrange .550.550.550.550 CopperCopperCopperCopper TinTinTinTin OrangeOrangeOrangeOrange .400.400.400.400 CopperCopperCopperCopper LeadLeadLeadLead OrangeOrangeOrangeOrange .280.280.280.280 CopperCopperCopperCopper Glass stirring Glass stirring Glass stirring Glass stirring

rodrodrodrod OrangeOrangeOrangeOrange .000.000.000.000

• An extension to this lab is to have the students attempt to light an LED with a series

circuit using multiple oranges and copper and magnesium strips. LED’s have different voltage and amperage requirements – select an LED with the lowest activation voltage and amperage possible.


1. Attach an alligator cord to the each lead of the voltmeter. 2. Check the settings on the voltmeter and insert the leads (check with the teacher if there

are any questions or you are unsure about the settings). 3. Roll the fruit on the tabletop to break up some of the tissue inside and create more

juice. 4. Insert a copper strip in the center of the piece of fruit to a depth of about 1.25 cm to 2.5

cm. 5. Insert a different type of metal strip about 2.5 cm away from the copper strip. Be careful

that the two strips of metal do not touch. The metal strips act as the electrodes for the battery.

6. Connect a lead to each metal strip (via the alligator cords). If a negative reading appears, switch the leads/cords.

7. Record the type of metals used and the voltage output. 8. Repeat steps #5 -7 using different types of metals in combination with the copper strip. 9. The larger the voltage reading, the more dissimilar the metals in terms of reactivity. 10. Rank the metals from most to least reactive based on the voltage readings. 11. Using copper and magnesium strips, hook two oranges up in a series circuit and record

the voltage output. 12. Predict the voltage output if three oranges are hooked up in a series circuit using

copper and magnesium. Make the series circuit and record the actual voltage output.

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13. Repeat step #12 using four oranges. 14. Optional: Attempt to light an LED using a fruit battery.

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Developing the Activity SeriesDeveloping the Activity SeriesDeveloping the Activity SeriesDeveloping the Activity Series

OverviewOverviewOverviewOverview:::: This is a group station lab. Students will be in groups of 4 or 5. Four different metal station labs are set up at the same time. Each rotation takes about 20 to 25 minutes. Each station will need an instructor/adult leader. Students look for signs of chemical reaction between copper II sulfate solution and six different metals. Students as a group rank the metals from most to least reactive – the results should parallel the outcome of the Fruit Battery lab. This lab also correlates with the Aluminum Can Liner demonstration and the Thermite in Your Hand demonstration. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• 0.2M copper II sulfate solution with non-iodized salt added • Five different metal strips cut into 1” pieces – magnesium, zinc, tin, lead and aluminum • Iron nails – 2 ½” bright nails

• 6 preforms or test tubes • Preform or test tube rack • Small plastic cups • Steel wool • Glass stirring rod


• Students should wear safety glasses during the lab. • Students should wash their hands after the lab.


• Aluminum is a very reactive metal but is slow to start in this lab. Aluminum oxide bonds tightly to the surface of the metal and acts like a protective coating. Adding sodium chloride to the copper sulfate solution keeps the oxide coating from forming and allow the aluminum metal to react with the copper sulfate . Add approximately 1.5 to 2 grams of non-iodized salt per 100 mL of .2M copper sulfate solution.

• The metal strips can be purchased from Flinn Scientific and cut into 1” pieces with scissors. Pre-cut the strips and put them in labeled cups. The nails can be purchased from a hardware store or home improvement store. The students will need to devise a method to keep track of which metal is which after they take them out of the cups.

• The students can divide up responsibilities to set up the lab. Two students can pour the copper sulfate solution into the preforms/test tubes while the other students clean the metal pieces with steel wool to remove oxidation and oil.

• As the students perform the lab and make observations the teacher will need to do a little “troubleshooting”. The students usually think the metals are “rusting”. The teacher will need to give guidance to get them to realize that it is copper metal being formed - not rust.

• An example equation for what is happening in the preforms is: Zn + CuSO4 ——> Cu + ZnSO4

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• The correct order for the reactivity of the metals from most to least is: o Magnesium o Aluminum o Zinc o Iron o Tin o Lead

• Copper is less reactive than the other metals and that is why it is replaced by them. The precipitate formed in the test tubes is copper metal.

• Metals are unstable as pure elements and therefore susceptible to oxidation/corrosion. More reactive metals can replace less reactive metals in compounds. Oxidized metals are in ion form and pure metals are neutral atoms.

• To clean-up, the contents of the test tubes can be poured into a large beaker. Add steel wool until the solution loses its blue color. The solids can go into the trash and the remaining solution can be poured down the sink.


1. Pour approximately 5 mL (or 1 inch) of copper II sulfate solution into each test tube. 2. Clean the 6 metal samples with steel wool to remove any oxidation. 3. Put a different metal sample in each of six test tubes one at a time so initial observations

can be made. 4. Record observations for approximately 5 to 10 minutes. Look for signs that a chemical

reaction is occurring: a. gas bubbles being produced b. temperature changes c. changes in color d. a solid precipitate forming e. solid disintegrating

5. Rank the metals in order of reactivity.

Zn Pb Fe Al Sn Mg

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Brassing a PennyBrassing a PennyBrassing a PennyBrassing a Penny

OverviewOverviewOverviewOverview:::: This is an individual station lab. Students will be in groups of 4 or 5. Four different metal station labs are set up at the same time. Each rotation takes about 20 to 25 minutes. Each station will need an instructor/adult leader. Students will zinc-plate two clean shiny pennies and then use a hot plate to create a brass surface by solid state diffusion on one of the pennies. The students may take the pennies home.

Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment: • Clean shiny pennies • Small glass bowl

• 1M NaOH • Granular zinc • Zinc strip • AA battery • AA battery holder with alligator clips • Plastic spoon with holes melted into the bowl of the spoon • Thick copper wire – about 4” long • Cups of distilled water for rinsing • Tarnex to clean pennies if needed • Plastic gloves • Hot plate • Tweezers or something to push hot penny into a cup of water


• Students should wear safety glasses during the lab. • Students should wash their hands after the lab.


• Brass is an alloy of copper and zinc. Alloys are mixtures of metals and at least one other element – most often another metal. Alloys are usually formed by melting the metals together and then pouring them into a mold to solidify.

• A very thin layer of zinc (several atoms thick) is plated onto the copper surface of pennies. In electroplating, positively charged particles from one material are removed and transferred through a solution until they are deposited on a negatively charged surface of another material.

• At the positive electrode (zinc strip), electrons leave the material creating positive Zn ions in solution. Electrons then travel through the power source to the negative electrode (copper penny).

• After electroplating, the pennies are heated on a hot plate. Heat causes the atoms to

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gain energy to the point where they are mobile enough to diffuse and mix together – forming the mixture brass. This is called solid state diffusion. The zinc and copper atoms have become a part of each other’s crystalline structure.

• Go to The City of Materials website - http://www.cityofmaterials.net/Default.aspx - for a virtual simulation of this lab as well as more background information on solid state diffusion and electroplating. Click on the “Menu and Info” tab and select “Science Center”. Click on “Visit the Science Center” and then choose “Fuel Cell Experiments”.

• Set-up for zinc-plating using cold solution: o Small glass bowl o Zinc strip – bent to lay flat on bottom of bowl, run up the side, and hang over and down the outside

o 1 M NaOH – deep enough to submerge the bowl of the spoon and penny and not have the spoon touch the granular zinc on the bottom of the bowl

o Granular zinc – cover the bottom of the dish • Melt holes in the bottom of a plastic spoon using a heated copper wire. This allows the sodium hydroxide solution to drain from the bowl of the spoon after plating and also allows better contact between the bottom of the penny and the solution.

• The spoon is easier to manipulate in and out of the solution if you heat the handle and bend it upwards to make a ladle.

• Make the solution the day before the lab to allow time for zinc ions to form in the solution. Or plate 2 or 3 pennies before the students do the lab to get the ions into the solution. The first penny may take up to a minute to plate. The second penny will take approximately 30 seconds. After the 3rd or 4th penny, it typically takes 10 seconds or less to plate each one.

• It works best if you submerge the penny in the solution and then firmly touch the copper wire to the penny.

• Also, it works best if you break the “circuit” before bringing the penny out of the solution.

• In other words, the penny shouldn’t be connected to the battery unless it is submerged in the NaOH/zinc solution.

• A quick decision needs to be made as to whether enough plating has been done. The “wet” penny needs to either go back into the NaOH solution for more plating or into a cup/beaker of distilled water quickly and not be exposed to air for any length of time with the NaOH still on it.

• Use fairly thick gauge copper wire for the electrode. • Best results are obtained when using brand new uncirculated pennies.

• It is crucial that all oxidation be removed from the pennies prior to the zinc-plating. • A product called Tarnex works great for removing oxidation. It can be purchased at local stores.

• Also, have students avoid handling the pennies after cleaning them. Oil from their fingers can leave a coating on the pennies that interferes with the plating.

• Caution the students about rubbing the pennies too hard after they are zinc-plated. Excess handling will cause the zinc-plating rub off. Once the brass is formed by solid state diffusion on the hot plate it will be resistant to wear.

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Procedure:Procedure:Procedure:Procedure: 1. Obtain 2 pennies. 2. If you have shiny new pennies rub the pennies with a dry paper towel to remove any oil from your skin. Do NOTNOTNOTNOT touch the pennies with your skin after rubbing them.

3. If your pennies have oxidation on them, clean the pennies thoroughly of all oxidation using Tarnex.

• You might want to wear plastic gloves when using Tarnex. • Wash the pennies with soap and water to remove the Tarnex and thoroughly thoroughly thoroughly thoroughly dry them.

• Do NOTNOTNOTNOT touch the pennies with your skin after washing them.

• Oil from your skin can keep the zinc from plating properly. 4. Go the zinc-plating station.

• In the glass dish is a mixture of 1M NaOH and granular zinc. • A zinc metal strip is submerged beneath the mixture and extends over the outside edge of the dish.

• Connect the DC voltage source (AA battery) by placing the positive alligator clip (red wire) on the zinc strip.

• Connect the negative alligator clip (black wire) to the copper wire. 5. Zinc-plating the pennies.

• Place one of the pennies in the “bowl” of a plastic spoon. • Submerge the penny in the 1M sodium hydroxide solution containing granular zinc.

• Do not touch the spoon to the granular zinc on the bottom of the dish. • Touch the copper wire (attached to the negative alligator clip - black wire) to the penny for a few seconds (start with about 8 seconds).

• Remove the copper wire from the penny and and and and the solution. • After all bubbling has stopped, remove the penny from the solution and quickly check the plating.

• Repeat as necessary to get full coverage. • The penny may need to be flipped over in the bowl of the spoon to fully plate the other side of the penny.

• Quickly rinse the penny in a cup or beaker of distilled water. 6. Repeat step #5 with the second penny. 7. Rinse the zinc-plated pennies under running water, gently rubbing them to make sure all of the sodium hydroxide solution is removed. Gently dry the pennies.

8. Set one penny aside for comparison. 9. Place the remaining penny on a warm hot plate.

• When a color change occurs, push the penny into a beaker of distilled water. • Dry the penny.

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FridayFridayFridayFriday

Wrap up grow beasts, test tube geology, borax crystals

• Make final observations • Wrap-up discussion • Students may take them home

Wrap up water gel crystals

• Students make observations and measurements • Wrap-up discussion • Students may take them home

Polydensity tubes and comparing water/rubbing alcohol – individual student lab

• Students experiment with the cohesive nature of polar molecules (water) and nonpolar molecules (rubbing alcohol) using wax paper, droppers, toothpicks, and salt

• Students experiment with the density of different plastics using mixtures of rubbing alcohol, water and salt

• Students may take the polydensity tubes home Pens through baggies with water – individual student lab

• Students push an sharp pencil through a sandwich bag filled with water • The polymer chains in the bag “window” to allow the pencil through without leaking

Test cement pucks

• As a group, the students determine what constitutes failure of a cement puck, i.e. loss of 20% of mass, loss of 25% of volume, x # of cracks, etc….

• Students drop the pucks from increasing height until they reach the defined failure parameters

• Final discussion/analysis of what types and placement of reinforcement worked best

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Separation Using DensitySeparation Using DensitySeparation Using DensitySeparation Using Density

OverviewOverviewOverviewOverview:::: Students work individually to make a polydensity tube. Observations are made and the students may take their tube home. The concepts of density, solutions, and nonpolar vs. polar molecules may be discussed during this activity. Materials and Equipment:Materials and Equipment:Materials and Equipment:Materials and Equipment:

• Preform and cap (one for each student) • Preform rack – 4 (one for each table or group) • Plastic pellets or beads – at least 2 kinds such as PETE (#1 recycling code), HDPE (#2

recycling code), PP (#5 recycling code) • 70% isopropyl alcohol (rubbing alcohol)

• Plastic pitchers with water • Kosher or canning salt in plastic cups with spoons or small scoops


• Students should wear safety glasses • Students should wash their hands after completing the lab.

Teacher Teacher Teacher Teacher Notes/Notes/Notes/Notes/Background/Background/Background/Background/Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:

• Gather plastic samples ahead of time. You can punch circles or cut small chips from plastic bottles, containers and lids to get a good mix of plastics. Try to get samples from at least 2 or 3 different recycling codes.

• It is also possible to get various kinds of plastic beads from a craft store. • Kosher salt or canning salt should be used as regular table salt has anti-caking additives

that cause the water layer to be cloudy. • Using plastic pitchers for the rubbing alcohol and water makes it easier for the students

to pour.

• The final tube will have two separate liquid layers. The polymer pieces will be at the top, middle or bottom based on their density.

• If there is no separation of fluids, add more salt - 95% of all problems have been solved by adding salt and shaking more.

• Rubbing alcohol is 70% propanol in water. Propanol dissolves easily in water because of the hydrogen bonding between the very polar water molecules and the somewhat polar 2-propanol molecules. Propanol is soluble in water in all proportions.

• When water is added to the rubbing alcohol in the preform, they mix and form a solution that is now less than 70% alcohol. This increases the density of the rubbing alcohol solution.

• Salt also dissolves in water. However, propanol does NOT dissolve in salt water. When salt is added to the solution in the preform, it dissolves in the water which forces the propanol out. This process is called “salting out” and has been used for years to purify alcohols.

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• The sodium and chloride ions from salt interfere with the hydrogen bonding between the alcohol and water molecules. Bonding between ions from salt and water is stronger and more favorable than the hydrogen bonding between alcohol and water.

• Salt, sodium chloride, is an ionic compound. In water, it dissociates into sodium cations (+ ions) and chloride anions (- ions). These ions are strongly attracted to the oppositely charged regions of the polar water molecule – more strongly attracted than the alcohol molecules are. Chloride ions and sodium ions sort of “elbow” the alcohol molecules -they push and shove them out of the way.

• When you add salt to the mixture, the propanol and salt water no longer dissolve in each other. They are “immiscible” and separate into two layers. The alcohol is less dense than the salt solution, so the alcohol will float on top of the salt-water. At this point the alcohol layer is approaching 100% propanol.

• Solids, such as HDPE, LDPE, PP, and PS, which are less dense than salt-water, but more dense than propanol, will float between the alcohol and the salt solution.

• Because both the liquids are colorless, the interface is difficult to see. It appears that the plastic pieces are "flinking" in the middle of a test tube full of water. If you look carefully you can see a faint white cloudiness at the interface where the alcohol and salt-water meet.

• The preform can be reshaken and the layers will miss temporarily and then separate again.


1. Add 2 or 3 pieces of each type of plastic provided by your teacher to your preform (plastic test tube).

2. Pour in rubbing alcohol (70% isopropyl alcohol) until your preform is just over half full. 3. Cap the tube and shake the mixture. Make observations. 4. Add water until the tube is a little over 3/4 full. Recap the tube, shake and make

observations. 5. Add a spoonful of salt to the tube. Recap the tube and shake. Shake a lot! And then

shake some more. Be patient, it takes a while for the salt to dissolve. 6. If all of the salt dissolves, add more salt and shake some more. There should be a little

bit of salt undissolved at the bottom. 7. Make observations. If there is no separation of fluids, add more salt and shake some

more.

(Acknowledgement: This activity is based on Polydensity Tubes® developed by Lynn Higgins, Polymer Ambassador.)

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Pens Through Baggies of WaterPens Through Baggies of WaterPens Through Baggies of WaterPens Through Baggies of Water (WOW (WOW (WOW (WOW –––– It Doesn’t Leak!)It Doesn’t Leak!)It Doesn’t Leak!)It Doesn’t Leak!)

Overview:Overview:Overview:Overview: This is an individual student lab. The activity will take 10 to 15 minutes. It can be used as an introductory polymer lab or as a quick filler when a short activity is needed.

MaterialsMaterialsMaterialsMaterials and Equipmentand Equipmentand Equipmentand Equipment:::: • Sandwich or quart baggie for each student • Pitchers of water • Sharp pencil or ball point pen for each student

• Sink, large bowl or bucket


• Students should be cautioned to not jab their hands with the pencil or pen

TeacherTeacherTeacherTeacher Notes/Notes/Notes/Notes/Background/Background/Background/Background/Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:Suggestions/Helpful Hints:

• Plastic baggies are made of long chain molecules called polymers.

• The long chain molecules can be “pushed apart” by a sharp object if it is wiggled with steady pressure. This allows the pencil to penetrate the baggie without breaking it.

• The students will sometimes burst their baggies so having a few extra is a good idea. • Doing the activity over a sink, large bowl or bucket will prevent having to clean up large

messes if a baggie does break. • Using a wriggling motion helps the pencil/pen find a “window” between the polymer

molecules. • The polymer molecules will seal around the pencil/pen and prevent water from leaking

out of the bag. • A similar activity is putting wooden skewers through an inflated latex balloon without

popping it. A small amount of lubricant such as oil is placed on the sharp tip of the skewer. The skewer is pushed (wriggled) through the bottom and top of the balloon where the latex is still “thick” and not overly stretched. The skewer is able to “window” between the latex molecules without popping the balloon. The molecules “seal” around the skewer and prevent the air from escaping – at least quickly. It will most likely slowly deflate over time. The instructor may want to demonstrate this after the students do the activity. Or do it as an “opener” before the students do the activity.

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ProcedureProcedureProcedureProcedure:::: 1. Fill a sandwich or quart baggie one third to one half full with tap water. 2. Seal the baggie. 3. Slowly and steadily push a sharpened pencil (or the tip of a pen) through the lower half

of the baggie (below the water level) while holding the baggie with the other hand. 4. Push the pencil/pen all the way through and out the opposite side. 5. Hold the baggie with one hand by the top and make observations. 6. Holding the baggie over a sink or large container and careful remove the pencil from the

baggie. Make observations.

Curriculum developed byCurriculum developed byCurriculum developed byCurriculum developed by::::

Debbie GoodwinDebbie GoodwinDebbie GoodwinDebbie Goodwin � Senior Master Teacher, Teachers

Camp � Member, Action in Education

Committee � George A. Roberts Award

recipient, 2008 � Distinguished High School

Teacher Award recipient

Goodwin, 2008 recipient of the George A. Roberts Award

Andy NydamAndy NydamAndy NydamAndy Nydam

� Senior Master Teacher, Teachers Camp

� Master Teacher since 2000, Materials Camp for students & teachers

� Trustee, ASM Materials Education Foundation

� First recipient of the Kishor Kulkarni Distinguished High School Teacher Award

Nydam accepting award from Dr. Kulkarni

****************************************************************

Facilitated and organized by: Jeane Deatherage

Administrator, Foundation Programs Materials Park, OH 44073 www.asmfoundation.org

800-336-5152

Our Mission:

To excite young people in materials, science, and engineering careers.

*************** The ASM Materials Education Foundation provides for the advancement of scientific and engineering knowledge through its support of education and research. Thanks to the hard work on the part of ASM volunteers and staff, the foundation is able to provide exciting opportunities for young people, encouraging them to pursue careers in materials, science, and engineering.

***************

Contact:Contact:Contact:Contact: ASM Materials Education Foundation

9639 Kinsman Rd. Materials Park, OH 44073

440 338 5151 www.asmfoundation.org

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CurriculumCurriculum - ASM Foundation · 2018. 3. 14. · Comments, criticisms, and suggestions are invited, and should be forwarded to ASM Materials Education Foundation. ASM Materials