Y-Chem Magic Show Certification Packet

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So, you want to do a “Magic Show!”
Student Presenter Packet for Y-Chem Outreach Program (10/11/2014)
INTRODUCTION
Thanks for your interest in sharing chemistry with the community! This packet is designed to
help you prepare and present safely and effectively. The documents in this packet will assist you in
planning and organizing your presentation:
DOCUMENTS (links):
1.
2.
3.
4.
5.
6.
Descriptions and presentation suggestions
Y-Chem Demo Request Form
Expectations
Safety Quiz
Presenter Training Checklist
Demonstration-Specific Instructions from LPL
CONTACT INFO
Scott Burt
Lecture Preparation Laboratory (LPL)
OFFICE: C008A BNSN
PHONE: (801) 422-2404
EMAIL: scott_burt@byu.edu
OFFICE: W136 BNSN
PHONE: 801-422-5807
LPL Hours: MWF 7-4 and TTh 7-2
PURPOSE
The purpose of the Y-Chem community outreach program is to inspire and motivate young minds
towards science and chemistry. Service to the community is also a goal of the university. In a way this
program also functions as an early recruiting tool, by demonstrating that exciting things happen at BYU.
While the visually stimulating demonstrations will no doubt enthrall audiences, education is just as
important as entertainment. You should start thinking about how you can use a memorable theme,
message, or story to teach something to the audience. Go to the next page, and start looking through the
demonstrations to see what is available and how each can fit your theme. The demonstrations are
grouped by potential themes. Feel free to use all or some.
NEXT: Decide which demos to use in section 1.
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1. Descriptions and presentation suggestions
Go through the following list of demonstrations and decide which items you would like to include in
your presentation. Mark the boxes of the demonstrations you are interested in performing. After
choosing the demonstrations you are interested in, read the instructions on how to perform the
demonstration in Demonstration-Specific Instructions from LPL to review more specific
information about each.
Potential Theme: “Chemistry is about change”
□ Simple clock
30 sec. after equal portions of two clear and colorless solutions are mixed together, the mixture changes to
a dark blue color.
Explanation/Teaching
 Color change is one way to detect that a chemical reaction has occurred.
 This is a complex chemical reaction, discussing the details of the chemical components
would be difficult, especially to elementary school children.
Presentation suggestions
 Option 1: Tell everybody that this is your favorite demonstration. Talk it up so that the students
are really excited. Ask them what they think will happen when you mix the two solutions.
Carefully add the two solutions. Stare at it for a second, and then look puzzled. Tell everybody
that it didn’t work, or that they “broke it.” Ask the other presenter if they made the solution
correctly. Blame them for it not working (clear it with them ahead of time), but some friendly
banter could be entertaining for the 30 seconds it takes to react. When it does, the class should
scream and shout. If they don’t, both of you can stare at the solution and look shocked.
 Option 2: Mix the chemicals, use a magic word, and then act puzzled when it “doesn’t work.”
Tell the students that it requires a different magic word. Ask each student in turn to say a magic
word to make it go. Each time that a student says a word and it doesn’t go, tell the class that it
must be a different word. When it finally changes, declare that they’ve found the right word.
□ Oscillating clock
When equal portions of three clear colorless solutions are mixed together, the resulting solution changes
colors in an oscillatory manner between orange and blue.
Explanation/Teaching
 This is a complex reaction involving several simultaneous reactions. One reaction generates blue
products, but another reaction is using up those products and producing yellow products.
Presentation suggestions
 Immediately after the components are mixed, quickly comment about how wonderful the yellow
color is, but look away before it turns blue. From this point on, only look at the solution when it is
yellow. Otherwise, look at it out of the corner of your eye as you ask them. When they tell you its
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blue, stall until it changes to yellow, and proclaim “See! It’s yellow!” A rule of comedy is that
antics are only funny up to three times.
□ Shaker bottles (advance prep required)
A clear colorless solution in a flask is vigorously shaken causing the solution to change color. Two flasks
are provided, one changes to a pink color, the other to a blue.
Note: Once prepared, this demonstration has a lifetime of about one hour.
Explanation/Teaching
 Chemical changes are sometimes shown by a color change
 Oxygen in the air dissolves in the solution, and reacts with an indicator.
Presentation suggestions
 Make sure the bottles are labeled (pink and blue
 Give the pink bottle to a girl, the blue to a boy, instructing them to hold the bottle tightly, but very
still. Then tell them to shake the bottles as hard as they can. If you like, you can say, “See,
chemistry is for boys and girls!”
□ Luminol
After equal portions of two clear colorless solutions are mixed, light emits from the resulting solution.
This solution is poured into a funnel connected to the top of a long plexiglass tube. The glowing solution
spirals helically downward and into a beaker.
Explanation
 Some reactions can release energy in the form of light.
 This is a similar reaction to that used in glow sticks.
Presentation suggestions
 Pour the reactants at equal rates down the spiral tower (provided by lecture prep)
- Make sure to put an empty beaker at the bottom
 Great with the lights out.
□ Universal Indicator
Dry ice is added to a purple solution. The solution proceeds through a sequence of color changes.
Warning: Dry ice will freeze skin and cause “burns”
Explanation/Teaching
 This solution is weakly basic and contains Universal Indicator, which changes color based on:
- [H+] or pH for older audiences
- “Chemical presence” for youngest audiences
 As we add dry ice, the CO2 dissolves in the water and reacts to form carbonic acid, which changes
the pH of the system, changing the color
 Basic condition is blue, acidic condition is yellow/peach
Presentation suggestions
 Add a small piece of dry ice first. If there is no color change within 5 seconds add a second
piece, and so on. You can add additional NaOH (if provided) to change solution back to purple.
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□ Calcium carbonate reaction
Two clear colorless solution are mixed, generating a white precipitate.
Explanation/Teaching
 Two colorless solutions create an insoluble compound.
Presentation suggestions
 CaCO3 is a main component of chalk. Other ideas might be cave chemistry, and hard water stains
on faucets.
□ Sodium polyacrylate
A powder is added to a small amount of water. The water quickly gels. Conversely, water can be added
to a plastic cup containing the powder; the cup is inverted without the water pouring out.
Explanation/Teaching
 This is the stuff found in diapers, it can absorb up to 200 times its weight in water
Presentation suggestions
 Put a small amount of the powder in the bottom of a white Dixie cup, and have a second Dixie
cup that is empty. Show the children that both cups are “empty” (the powder will blend in with
the cups and they won’t see it). Pour a small amount of water into the truly empty cup, and then
pour it from the empty cup into the cup with the powder. Attempt to pour the water back into the
other cup, and ask “Where did the water go?”
□ Memory Wire
A piece of wire in the shape of a block letter “U” is dropped into a bath of boiling water. The wire
immediately changes shape to a block letter Y. The wire can be easily shaped and bent, but when
returned to the boiling water, quickly forms the block letter “Y.”
Warning: Care must be taken to with the hot plate needed to generate the boiling water to avoid burns
and fires.
Explanation
 Elementary School: Browse for the story of how it was discovered by William J. Buehler, a
researcher at the Naval Ordnance Laboratory, and summarize your findings.
 High School: Explain that there are two solid phases, and when you heat it above a certain
temperature, it changes to the second phase, which moves to a more energetically favorable
orientation (the shape you have pre-set)
Presentation suggestions
 Hold up the U again a contrasting background. Ask the students “What happens when you put
the heat to the U?” Carefully drop the wire frame into the boiling water so that it lands flat (if
you don’t it can violently jump out). Using tongs, pull out the wire, hold it against the high
contrast background, and declare, “The Y comes out on top!”
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Potential Theme: “Chemistry is cool, and hot!”
□ Gun cotton / Regular cotton
Commercial cotton is ignited on a ceramic tile. The cotton slowly burns. Chemically modified cotton is
also ignited on a ceramic tile, but erupts quickly in a bright, fiery flash.
Warning: Some batches burn slower than others. Only ignite the cotton on the provided tile.
Explanation
 Cotton is made of cellulose, which burns slowly.
 When cotton is soaked in fuming nitric acid, the hydroxyl groups are replaced by nitro groups,
making it combust much quicker (the same step used to make the ‘N’ in ‘TNT’).
Presentation suggestions
 The following is from the Wikipedia article on gun cotton:
- Christian Friedrich Schönbein, a German-Swiss chemist, discovered a more practical
solution around 1846. As he was working in the kitchen of his home in Basle, he spilled a
bottle of concentrated nitric acid on the kitchen table. He reached for the nearest cloth,
a cotton apron, and wiped it up. He hung the apron on the stove door to dry, and, as
soon as it was dry, there was a flash as the apron exploded.
(http://en.wikipedia.org/wiki/Gun_cotton)
 Great with the lights out.
□ O2 balloon cooled with liquid N2
A balloon filled with oxygen is lowered into a dewar filled with liquid nitrogen. The balloon almost
completely deflates. When the balloon is removed from the dewar, the balloon re-inflates.
Warning: Liquid nitrogen is much colder than dry ice, and will quickly freeze and burn skin. Be
aware where the liquid nitrogen drips.
Explanation/Teaching
 Oxygen gas turns to a liquid at the temperature of the liquid nitrogen. There are no molecules
pushing on the inside of the balloon to keep it inflated.
Presentation suggestions
 If you can form the long balloon into a shape (like a dog or a sword – quite easy, ask Dr.
Macedone to show you), the audience can be a little more involved as you deflate the structure in
the liquid nitrogen.
□ Mg ribbon
When a strip of magnesium metal is ignited with a blow torch, the metal burns and intense and brilliant
white. Students can see the spectrum using diffraction glasses.
Explanation/Teaching
 The magnesium metal is hot and reacting with oxygen in the air.
 This is the bright white color in fireworks.
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Presentation suggestions
 The visual appeal of the burning magnesium wire is enhanced by viewing the event through the
diffraction glasses, suggest looking slightly to the side of the ribbon.
 Great with the lights out.
□ Collapsing can
A 5 gallon can strong enough to stand on collapses under atmospheric pressure. A small amount of water
is added to the can, and boiled, filling the can with hot air. The can is corked, and spun in a tray of ice.
The can collapses like an aluminum can.
Warning: Your hands could be crushed if caught in the collapse. Make sure the can is spun
using the sides of the can.
Explanation/Teaching
 When we boil water inside the canister, water vapor is displacing air. In addition, the water vapor
is hot. When the can is stoppered, and the water vapor is cooled from steam to water. There are
now fewer molecules pushing on the inside of the container than on the outside of the container
from atmospheric pressure.
Presentation suggestions
 Put on the orange heat gloves. Stopper the can very well. Pound it a bit, but don’t hurt your
hand. Quickly but carefully stand on it to show that it is strong.
 Be careful if the gloves are wet. Wet gloves are not good thermal protection from hot objects.
□ Methanol Cannons
A small amount of methanol is added to 500 mL bottles, and the bottles stoppered. A spark is delivered
to the resulting methanol vapor via nails driven in the sides. The methanol vapor ignites, and pops off the
stopper with “bang.”
Warning: The telsa coil spark source is an electrocution hazard, handle with care.
Never shock yourself deliberately with the tesla coil.
Explanation
 Combustion - this is a similar reaction to what happens in your car
 Fuel and oxygen are mixed, but they don’t react until you provide energy
Presentation suggestions
 Put the methanol in, and then stare at the cannons, waiting for something to happen.
 Ask why nothing happens
 Explain that you have to provide the energy to start the reaction.
 Turning out the lights can accentuate the flash from the cannons.
□ Flaming Tornado (12’ ceilings required)
This demonstration generates a 4-5’ tall vortex of fire. A dish of ethanol is spun with a hand crank on the
device.
Warning: be aware of close by materials which could ignite (e.g. curtains, ceiling)
A 12’ ceiling is required to do this demo!
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Explanation
 Combustion is a chemical reaction
 The methanol is reacting with the oxygen in the air to produce water, carbon dioxide, and heat.
 Oxygen from the air is required for the reaction. O2 is drawn through the screen which causes the
flame to spin in the horizontal direction. At the same time, the reaction is producing heat, which
causes the product gases to rise; this is vertical component of this spectacular demonstration.
Presentation suggestions
 Light the methanol, but do not turn the hand crank.
 Act like it’s the coolest thing that you’ve ever seen, and wait for someone to say “That’s boring!”
Then start it up.
 Turn out the lights to enhance the splendor.
Miscellaneous
□ Discharge lamps
A high voltage power source generates light emission from various gas tubes. Diffraction glasses are used
to observe the spectral differences between the various gases. (H2, He, Ar, Kr, Xe, etc.)
Explanation
 Electricity is exciting the electrons to higher energy levels – atomic spectra discussion
Presentation suggestions
 Be careful to hold the discharge tubes by the bulbous part, but not the metal end of the tube. You
could be shocked if you forget to turn off the power supply when changing bulbs! Also, be
careful the bulbs get quite hot during use.
□ Elephants Toothpaste
A catalyst is added to a solution of hydrogen peroxide and soap. The accelerated reaction generates a
large amount of oxygen causing foam to shoot out of the graduated cylinder holding the original soaping
solution.
Warning: the foam is hot for a few minutes and stain skin and clothing
Explanation
 The graduated cylinder contains H2O2 which is already reaction, but very slowly
 When you add a catalyst, it speeds up the reaction.
Presentation suggestions
 Tell the students that there’s a reaction going on in the graduated cylinder. Ask them if they can
see it, and then point out that they can’t see it because it’s too slow.
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□ Slime
Two clear colorless solutions are added in 1:10 proportions (see bottles). A polymerization reaction
proceeds, generating a slimy product safe to handle.
Note: if you choose to use food coloring, be careful of staining clothing, etc.
Explanation
 Chemistry is used to make polymers long chains of repeating units that stick together well
Presentation suggestions
 This is safe for students to touch.
□ Density balloons
The principle of density is demonstrated with three balloons of equal volume. The masses are quite
difference because they are filled with helium, air, and sulfur hexafluoride.
Under no circumstances inhale any of these gases!
Explanation
 Density is a measure of the mass of a given volume of a substance.
Presentation suggestions
 The contrast of buoyant, neutrally buoyant, and non-buoyant balloons is fun. You can toss the
SF6 balloon around like a beach ball, so the students can see it feels like it has water in it.
□ Nylon rope (no student contact)
Two clear colorless solutions are added to a container forming two phases. Tweezers are used to grab a
white film which forms at the phase boundary. As the white film is pulled from the solution, it forms a
strand of nylon which is draped around a drum. The drum is turned and a continuous supply of nylon
rope is generated.
Warning: These chemical are quite toxic, use the nitrile gloves provided.
Explanation
 This is another example of polymerization
Presentation suggestions
 The invention of Nylon 6,6 (A similar compound) changed dentistry
- Before nylon, toothbrush bristles used to be made of boar hair (wait for a
“grooooooosssss!” from the audience.
 Do not let the students touch the components or the product.
NEXT: Transfer your selections to the next section.
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2. Y-Chem Demo Request Form
Fill out 1-6. When you eventually submit this form to the LPL (W136 BNSN) you will need to provide a
minimum of 24 hrs notice. After filling out this form, go to section 3, Expectations.
1. PICK UP on: __/___/__ at __:___ am/pm
2. Lead presenter: ____________________Assistant presenter: ___________________
(completed Chem 201)
(Chem 201 not required)
3. Location of “Magic Show:” _________________________
4. What is the policy at this location regarding igniting an “open” flame indoors?
________________________________________________________________________
5. Describe your travel plan: (what automobile(s) will be driven by whom?)
________________________________________________________________________
6. Please check the demonstrations to be performed (if not listed see “other”)
 Simple clock
 Oscillating clock
 Shaker bottles
o in flasks (<1hr!)
o prepare at show
 Luminol
o Tower
 Dry ice w/
universal indicator
 CaCO3 precip.
 Sodium polyacry.
 Memory Wire
o Hot water
o Hair dryer
 Cotton / gun cotton
 Liquid nitrogen
o O2 balloon
o Rubber nail










OFFICE USE ONLY
Mg ribbon
Collapsing can
Methanol Cannons
Flaming Tornado
Discharge lamp
Diffraction glasses
How many?______
Elepha. Toothpaste
He, air, SF6
Slime – PVA
o Food dye
Other (specify):
________________
________________
Include w/ each show
 Nitrile gloves (4 pair)
 Waste container
 Fire extinguisher
 Heat gloves
 Tongs
__________OUT
(time)
__________ REC’D
(time)
__________ALL EQ.
(initials) RETURNED
Return to Dr. Burt!
______ (init.) Magic show plan reviewed by Dr. Bronson
______ (init.) Certifications verified by Dr. Burt
SPECIAL INSTRUCTIONS: ___________________________________________________________
_____________________________________________________________________________________
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NEXT: Read and know the Expectations in the following section.
3. Expectations
When you visit elementary schools and other venues, you are a representative of Y-Chem and the
University. It is expected that you will represent the University, the Chemistry Department, and Y-Chem
responsibly and honorably. Part of that effort includes making responsible choices before, during, and
after a “magic show.”
BEFORE
Read and study demonstration instructions.
Complete LPL magic show training
Plan your “Magic show”
 What is the theme of the Magic show?
 How will you explain and describe each demo?
Design your travel plan:
 Carpooling is encouraged
o One exception is that BYU policy states that if both traveling
students are married, but not to each other, and they are of the
opposite sex, they must take separate vehicles.
 Store all chemicals in the trunk of your car, away from people.
 Transporting liquid nitrogen is a potential suffocation hazard. Keep the
windows open enough to ventilate the cabin.
Review plan with Dr. Burt >2 days in advance (yes, for every show)
Notify LPL - turn in the completed request form (at least 2 days in advance)
 This service is not available during National Chemistry Week, and some
other weeks due to high volume requests from PS100.
Scope out where you will place experiments involving fire. Place away from
all flammable items such as curtains, etc.
Never do unauthorized experiments.
DURING
FIRST give the “do not try this at home” speech.
Warn audience before loud noises and flashes.
Presenters MUST wear splash guard goggles, not simple safety
glasses AND a lab coat.
 See examples at right: top set OK, bottom no way.
 Lecture Prep will supply goggles and lab coats
Keep the fire extinguisher in a readily accessible place in case of
a fire. This will be provided by the LPL with every demonstration
If you are presenting, be cautious, pay attention to what you are doing.
If NOT presenting, be a “spotter” for your partner; watch for problems and
ways to assist.
Never encourage others to smell, inhale, taste, or handle chemicals.
Never degrade or use sarcasm toward disruptive audience members.
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AFTER THE SHOW . . .
When chemicals are in use or uncontained, wear goggles and lab coat.
Prevent the audience from touching the demonstrations or chemicals!
 After the magic show is over, if needed stand IN FRONT of the demos
 Answer questions responsibly. Remember that some children will have a
desire to go home and experiment on their own; focus on the chemistry
not the recipe. We don’t want kids going home and trying to make
thermite on their own.
Dispose of all waste in the waste container provided.
 Even if a demo says you can flush something down the drain,
don’t. Pouring chemicals down the drain, although safe with
most of these chemicals, isn’t setting a good example for
school children. Place all liquid spend demonstrations in the waste
container provided. Return the full waste container to Lecture Prep. Do
not dispose of the waste yourself.
o EXCEPTIONS: Elephant’s toothpaste can get very messy if not
cleaned up immediately. Be sure that a sink out of sight of
students will be accessible, so that you can wash the foam down
the sink (using gloves).
Promptly return all items to the Lecture Prep Laboratory
 Promptly means the day of the demo, if at all physically possible. At the
very latest, very first thing the next day. Any later than that puts an
unacceptable burden on the Lecture Prep Lab staff’s ability to be of
service to the faculty.
NEXT: take the Safety Quiz
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4. Safety Quiz
NAME:____________
Complete the following questions to demonstration your understanding of the information
presented in the packet. This is a quiz on the contents of the safety packet as well as the
training presentation. It is open packet/notes, and you may consult with Dr. Burt if you have
questions. Any questions missed will be reviewed orally at your plan review with Dr. Burt.
1. What is the purpose of Y-Chem Magic Shows?
2. How many demonstrators (minimum) are required to be at every magic show?
3. Name three mandatory safety equipment items that must be present/worn for prep, show,
and clean-up?
4. Explain proper disposal of the following demonstrations:
a. Oscillating clock
b. Elephant’s toothpaste
5. How far ahead of time can you mix solutions A and B for shaker bottles?
6. What should be done with the waste container once your magic show is over?
Circle one:
A.
B.
C.
D.
E.
Dump it down the drain.
Return it immediately to the Lecture Prep Laboratory for disposal.
Call waste management and have them pick it up.
Take it home as a pillow.
Sell it to the highest bidder at the next elementary school
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7. Explain what precautions must be taken with the flaming tornado.
8. What precaution must be taken when using the heat gloves?
9. When performing the collapsing can demonstration, how should you grip the can?
10. What is the one experiment that is safe for children to touch?
11. What precautions must be taken when transporting the materials and chemicals for the
show?
12. What are potential hazards for the methanol cannon demonstration?
13. How many days in advance of the show must you meet with Dr. Burt to review the show
plan?
14. What do think is a question we should have asked on this quiz, but didn’t?
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NEXT:
It is very important to fill out this form:
http://tinyurl.com/YCHEMPresenterForm
If you do not fill out this form, you will not be notified for Magic Show
opportunities.
Now, set up a meeting with Dr. Burt by email (scott_burt@byu.edu) with the
subject line “Y-Chem Training Interview.” Include in your e-mail likely times you
could meet.
PRINT and bring to interview with Dr. Burt:
Section 2. Y-Chem Demo Request form
Section 4. Safety Quiz (first- time only)
Section 5. Presenter Training Checklist
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5. Presenter Training Checklist
Fill out the following form and bring it with you when you review the show with Dr. Burt.
While performing magic shows, I will follow the guidelines outlined in this packet, I will be
responsible, and use common sense. I also promise to try to have fun!
NAME: _______________________________ DATE: _____________
E-MAIL: __________________________________ PHONE: ______________ GRAD DATE:_____
THE FOLLOWING ARE FOR OFFICE USE ONLY:
□ Y-Chem Member
□ Read documents
□ Attended training session
□ Passed training quiz
□ Interviewed by Dr. Burt
Assistant Presenter Approved!
____________________________
Scott Burt, PhD.
_______________
Date
□ Assisted with a magic show (required to be lead presenter)
□ Passed Chem 201 (required to be lead presenter)
Lead Presenter Approved!
____________________________
Scott Burt, PhD.
_______________
Date
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6. Demonstration-Specific Instructions from LPL
The following are the instructions the LPL has on file for the demonstrations mentioned
above. Preparation instructions of the solutions you will be using have been omitted for
clarity.
Simple Clock
Two colorless solutions are added together. After some time, the resulting solution suddenly turns blue.
Equipment
Two solutions are needed; one is labeled “Simple Clock A,” the other is labeled “Simple Clock B”. You
will also want a 300-mL or 400-mL beaker.
Safety
Sulfuric acid should always be handled with care because it is a strong oxidizing and dehydrating agent.
Dilution of sulfuric acid from a concentrated form is an exothermic process. Sulfuric acid will damage
clothing and skin.
Sodium bisulfite is a strong reducing agent and an irritant to mucous membranes. Do not mix sodium
bisulfite with acid (a toxic gas is evolved). Potassium iodate is a strong oxidizing agent and can be
flammable and explosive.
Disposal
Put the solutions into the supplied waste container.
Chemistry
The color change is initiated by a sudden increase in the number of triiodide ions (I3-) in solution when
the bisulfite has been consumed. The blue starch-triiodide complex is formed in the final of four steps.
IO3- + 3 HSO3-  I- + 3 SO3 + 3 H+
IO3- + 8 I- + 6 H+  3 I3- + 3 H2O
3 I3- + HSO3- + H2O  3 I- + SO42- + 3 H+
2 I3- + starch  starch- I5- complex + IPresentation
Pour equal portions of Solution A and Solution B into the beaker. Tell your audience to watch closely or
else they will miss the color change. The solution will change from colorless to suddenly dark blue in
about 10 seconds.
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Oscillating Clock
Three colorless solutions are added together and the resulting solution oscillates between clear, blue, and
yellow.
For presentation
Deliver 400mL beaker and bottles labeled Oscillating Clock A, Oscillating Clock B, and Oscillating
Clock C.
Safety
Perchloric acid is a skin irritant. Potassium iodate is a strong oxidizing agent and mixtures with
combustible can be flammable or explosive.
Disposal
Put the solutions into the supplied waste container.
Presentation
Pour equal portions (100mL) of Solutions A, B, and C in to the beaker. Make sure it is in the order of A,
then B, then C. The new solution will oscillate between colorless, yellow and blue.
Misc. notes/Performance
If you don’t dispose of the oscillating clock right away, elemental iodine will accumulate at the bottom of
the flask. This can be done on an overhead to allow larger classes to see the color changes. The solutions
must be added in the correct order for the reaction to occur.
Shaker Bottles
Bottles with dextrose, potassium hydroxide, and indicator change color when shaken as the
indicators react with the oxygen gas dissolved into the solution.
Set Up
Add two parts of solution A and 1 part of solution B into each of the 1L bottles. To the first add ~1 ml
methylene blue dye ( like 2 crystals), to the second add ~0.5 ml resazurin (like 2 crystals), and to the third
add a small scoop of indigo carmine. Cap the bottles. Use within about 1 hour of setting up. If
solutions turn yellow, they are no longer useable.
Safety
Be careful not to get indicators on clothing---they will stain. KOH is a strong base. Do not use
KOH in glassware except in very dilute concentrations.
Disposal
Don’t leave solutions in bottles, or they will be stained and useless in future demonstrations. Put the
solutions into the supplied waste container.
P a g e 17 |
Chemistry
Methylene blue acts as a catalyst for the oxidation of dextrose by gaseous oxygen, and the other indicators
act similarly. The color changes observed are due to reversible oxidation and reduction of the dyes.
Methylene blue is colorless in the reduced form and blue in the oxidized form. It is thought to be reduced
to the colorless methylene white by dextrose, and the shaking of the bottle dissolves oxygen into the
solution, oxidizing the dye back to the blue form. If allowed to stand, the dye will be again be reduced by
dextrose.
Rezasurin first undergoes an irreversible reduction by dextrose to resorufin, which is fluorescent red.
Then it undergoes a reversible reduction to colorless dihydroresorufin, which is readily oxidized back to
the fluorescent red resorufin.
The yellow color that forms after time is the decomposition products of dextrose.
Presentation
Shake the bottles and the color changes in the following manner:
Added:
Change:
Bottle #1
1 ml Methylene Blue
Colorless to blue
Bottle #2
0.5 ml Resazurin
Colorless to pink
Misc. notes/Performance
Keep KOH stored in tightly capped bottles to prevent the concentration from changing. Do not allow the
pre-made mixtures to stand for extended periods of time before using in the demo.
Dry Ice Acid/Base Indicator Solutions
Acid/base indicators show the change in pH of a solution from basic to acidic conditions as
carbonic acid is formed from dry ice.
Safety
Be cautious with the dry ice, as it will burn skin. Also, be cautious with the solutions which will be
acidic.
Disposal
Put the solutions into the supplied waste container. Leave dry ice in the supplied container and return
to the LPL.
Chemistry
Each indicator solution starts out basic. Addition of dry ice (solid CO2) causes the formation of carbonic
acid, making the solution more acidic and causing the indicators to change to their acidic color.
CO2(s) + H2O (aq) ↔ H+(aq) + HCO3- (aq) ↔ H2CO3 (aq)
P a g e 18 |
Presentation
Add a few chunks of dry ice (broken up before presentation with a hammer) to each fleaker, and watch as
the color changes. CO2 will also form at the top of the fleaker.
Calcium Carbonate
When sodium carbonate and calcium nitrate are mixed, the insoluble compound calcium carbonate is
formed.
Safety
Do not drink.
Disposal
Put the solutions into the supplied waste container.
Chemistry
Net ionic equation:
Ca2+ (aq) + CO32- (aq) CaCO3 (s)
Presentation
Point out that the solutions are starting out clear and colorless. Slowly add one solution to the
other.
Sodium Polyacrylate
This compound absorbs and retains as much as 200 – 300 times its mass in water, and is the absorptive
component found in diapers.
Disposal
Leave solid in cup. Return to LPL, and they will dispose of it.
Safety
Skin Irritant. Avoid inhalation of the powder.
Chemistry
Sodium polyacrylate consists of long hydrophobic carbon chains with lots of sodium ions in the middle.
When you add water, it is drawn into the middle via osmosis to lessen the high concentration of sodium in
the middle of each polymer. The water is then trapped within the hydrophobic carbon chain resulting in
sodium polyacrylate’s ability to absorb and retain large amounts of water.
Presentation
Add the sodium polyacrylate to the beaker of water and stir with the stir rod. Show to the class that the
water in the beaker has been completely absorbed by the sodium polyacrylate to form a solid gel-like
substance.
P a g e 19 |
You may also try a bit of showmanship by putting a small amount of sodium polyacrylate in a white
dixie- or styrofoam cup. Take an identical cup without any sodium polyacrylate. Show the students inside
the cup briefly. The sodium polycarylate will not be visible against the white interior of the cup. Put a
small amount (100-200 mL) of water in the empty cup, and then pour it into the other cup. Then try to
pour the water back out. Ask the students “Where did the water go?”
Memory Wire (U to Y)
Memory wire is bent into a letter “U” or any desired shape. When placed in boiling water or suspended
above steam, the wire snaps to the letter “Y” to represent BYU.
Set Up
Shape the memory wire into the “U” (using the mold, with the wire welds at the bottom of the U to
prevent the wire from springing out of the water as it changes shape) or into any desired shape. Boil 2-3
inches of water on a hot plate. Place memory wire next to hot plate with tweezers.
Safety
Be careful with boiling water.
Clean-up/Disposal
Remove the wire from the water, and pour out the water. Re-form the memory wire to the U shape and
store it with the mold.
Chemistry
Memory wire is a patented Nickel-Titanium alloy called NiTinol. NiTinol memory metal has two
crystalline phase forms with a transition temperature between 30º and 50º C. Below the transition
temperature, the memory wire is in a solid phase that is flexible, called the Martensite phase. Above the
transition temperature, the NiTi alloy prefers the Austenite phase which is characterized by its rigidity.
The memory wire alloy crystal consists of tiny planar areas called crystallites. Several metal atoms are
bound together as one small cluster of metal atoms. When the wire is bent below the transition
temperature, the bonds between the crystallites flex slightly.
When the alloy is heated into the Austenite phase, the planes are slid back into place and the structure
reverts to its original form. The Martensite structure has 24 different variants to carry out this
transformation and, as a result, can be deformed in nearly any direction. Thus, the metal appears to
'remember' its original shape. However, if the wire is bent at a temperature above 500 °C, the crystallites
reorient to take on a new shape.
P a g e 20 |
This new shape can also be bent at temperatures below the transition phase.
As the wire is heated to the Austenite phase, the wire will remember this new set shape.
Presentation
“U to the Y”: Drop the “U” shaped piece of memory wire into the boiling water. It will immediately reform into the “Y.” Pull out with tweezers and present to the class. The experiment does not work well at
temperatures below 80 °C. The punchline of the demonstration is “when the heat is on, the Y will always
come out on top” or something similar.
If a slower reaction is desired, suspend the “U” above the steam with a ring stand. It takes approximately
5 minutes for U to slowly morph to the Y.
Gun Cotton (Nitrocellulose)
Cotton is soaked in an acid solution to form nitrocellulose, which completely combusts in a smokeless
flame.
Safety
When preparing gun cotton, do all steps in the hood. Toxic gases may evolve. Use caution when
working with concentrated acid solutions, they are extremely corrosive. Never ignite the Gun Cotton in
your hand.
Disposal
After the ashes and charred remains have cooled down (be sure of this), dispose of them in the trash.
P a g e 21 |
Chemistry
Gun cotton is nitrocellulose C6H7N3O11 cotton. Cotton balls, which is 90% cellulose C6H7O5, are
placed in fuming nitric acid. The hydroxyl groups on the cellulose are replaces with nitro groups.
O
-
H
+
N
HO
O
H
O
+
3 HNO3 (aq)
O
O R
R
OH
+ 3 H2O (g)
N
H
OH
O
+
R
H
H
H
O
cotton goes up into a ball
complete combustion.
-
R
O
H
O
+
N
H
O
-
When lit, the
of smokeless flame from
Presentation
Burn cotton on the ceramic tile, then, using tongs, grab some gun Cotton and set it on the remaining
smoldering cotton. It should go up in a flame immediately.
Collapsing Can Demonstration
This demonstrates atmospheric pressure by creating a partial vacuum in a can, causing external
atmospheric pressure to crush it.
Set Up
Fill the can with about an inch of water and then set it on top of the hot plate with the hot plate on high
(l0). It will take at least 10 minutes for the water to be heated enough to where it is readily
streaming out of the can. Have the ice tray nearby.
Safety
Boiling water can cause burns, so use the orange heat gloves to hold the can. DO NOT ALLOW THE
HOT GLOVES TO GET WET, OR THEY WILL CEASE TO INSULATE!
Disposal
Empty water from can into drain. Dump the ice down the sink.
Chemistry
Water vapor replaces the air in the can as it is heated. When the can is sealed and cooled, the vapor
condenses, creating a low-pressure system on the inside of the can. The relatively high pressure outside
the can causes it to be crushed.
Presentation
Do not attempt until steam is visibly coming out of the top of the can and has boiled for a few minutes to
push the air out and allow the water vapor to fill the can, but do not let it boil to dryness Wearing gloves,
take the can off the hot plate and tightly stopper the can. Put the can in the ice, and roll it to get the best
results. The can will implode quickly. Watch your fingers! DO NOT THE WALLS OF THE CANONLY HANDLE LID AND BASE- OTHERWISE YOUR FINGERS WILL BE PINCHED WHEN THE
CAN COLLAPSES.
P a g e 22 |
Flaming Tornado
Burning alcohol in a beaker surrounded by a mesh wire column, a vortex of fire is generated.
Using inorganic salts the color of the vortex can be changed.
Set Up
Bring out all equipment. Place crystallization dish inside the metal beaker in the middle of the turntable.
Pour about 300 mL ethanol into beaker. Add a small amount of an inorganic salt (or a combination).
Some choices include CuCl2 (green), KMnO4 (purple), LiF (magenta), NaCl (yellow) and SrCl2 (red).
Place mesh cover next to apparatus.
Safety
Be very careful with the apparatus after you start the flame – the metal can get very hot. If the apparatus
runs for long enough the glass may break. If this occurs clean up the pieces carefully.
Clean Up
Ensure that all the ethanol has dried/burned before transporting the tornado. No cleanup is required.
Chemistry
When atoms are exposed to heat, their electrons are excited and promoted to a higher energy level. As
they return to their lowest-energy state, they emit the extra energy as photons (light packets). Each salt’s
unique color corresponds to its elements’ own differences in energy levels.
Presentation
Use the lighter to ignite the ethanol. Place the aluminum mesh over the apparatus, sliding it into the
sheath. Turn out the lights and turn the handle of the apparatus. The ethanol initially burns yellow. The
flame will change colors as the salt(s) diffuse. Abruptly stopping the turntable and then turning it the
other direction often shows a color change. To extinguish the flames, remove the mesh with caution as it
may be hot, and cover the beaker with the pie dish.
Elephant’s Toothpaste
A small amount of KI is put into a solution of hydrogen peroxide and dish soap, and yellowish-white
foam shoots out of the graduated cylinder.
Safety
This demo is exothermic and the foam created has 30% hydrogen peroxide in it. Do not touch it or allow
anyone else to do so. Also be careful when setting up and demonstrating not to use too much solution,
because it will overflow the plastic tray and make a mess.
Disposal
Wait until students are gone, and (using the provided gloves) wash this demonstration out in a large sink
(ask if there’s a janitor’s closet you can use) Wash everything in the sink; all the chemicals can be
disposed of that way.
P a g e 23 |
Chemistry
This reaction demonstrates the decomposition of hydrogen peroxide (H2O2) with a potassium iodide
catalyst. It is a two-step reaction:
H2O2 (aq) + I – (aq) → H2O (l) + OI – (aq) (rate determining step)
H2O2 (aq) + OI – (aq) → H2O (l) + O2 (g) + I- (aq)
The brown, yellow color of the foam indicates the presence of iodine in solution as the I3-(aq) species as a
possible side reaction.
The dish soap just acts to collect the oxygen gas as it is evolved.
Presentation
Make some comments about having elephants and needing toothpaste and then dump the KI into the
graduated cylinder.
Nylon Rope Demonstration
A nylon thread is formed when two immiscible liquids are mixed. The nylon rope can be pulled to
extensive lengths using forceps or wound on a windlass (crank).
For demonstration
Gather two 1 liter stock bottles, one labeled “Nylon Rope Top Solution”, and the other labeled “Nylon
Rope Bottom Solution”. Also, set out the windlass on a stand.
Safety
All these reagents are very toxic and cause nausea. Make sure you prepare all of these solutions in the
hood and wear protective eyewear and gloves.
Chemistry
Nylon, or synthetic polyamides, are formed from diamines and dibasic acids and are designated by one
number for each. In this demonstration we form 6-10 nylon with hexamethylenediamine and sebacic
acid, although the sebacic acid is represented by sebacoyl chloride in the reaction shown:
H2N(CH2)6NH2 + ClCO(CH2)8COCl  [HN(CH2)6HN-CO(CH2)8CO] + 2 HCl
This type of reaction is called interfacial polycondensation. It is especially useful because it is a low
temperature process, and will react rapidly at room temperature. Another beneficial component of this
reaction is that it does not require exact stoichiometric ratios.
Nylon 6-6, a commercially used polyamide, can be made by substituting adipoyl chloride for sebacoyl
chloride.
P a g e 24 |
H2N(CH2)6NH2 + ClCO(CH2)4COCl  [HN(CH2)6HN-CO(CH2)4CO] + 2 HCl
P a g e 25 |
Presentation
Pour some of the bottom solution into the beaker, then pour an equal amount of the top solution onto the
bottom solution. With the tweezers, grab the interface between the two liquids and pull it up and above
the beaker. Begin to twist the tweezers to show the continuous thread of nylon formed or use the windlass
provided to wind it.
To show the interface better, use food coloring or phenolphthalein in the bottom solution.
Disposal
Place the solutions in the appropriate “nylon rope” waste.
Misc. notes/Performance
The nylon rope can be stretched to great lengths. To emphasize this, you can put the beaker on the floor,
stand up on the desk, and use the forceps to pull the nylon as high as your arms can reach. The string can
then be wound around a windlass to further demonstrate the length.
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