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Total Internal Reflection
Introduction
A laser beam is reflected inside a falling stream of water.
Materials
• Red/Green laser
• 2 Liter soda bottle with cap
• 2- Ring stands
• 1-thermometer clamp
• Iron ring
Procedure
• Prepare a 2-liter soda bottle by piercing a small hole approximately 2 inches from the base of the bottle. Try and
make the hole as round as possible to allow for a continual stream. Insert the laser into the thermometer clamp.
• Place the soda bottle into the other iron ring. The laser should be in alignment with the hole, which should be on
the opposite from the laser.
• After the setup is complete, place a piece of tape or hold a finger over the hole and fill the bottle with water and
cap it. When ready to start the demonstration, turn on the laser which should be in alignment with the whole on
opposite side, Turn off the room lights, and carefully loosen cap slightly to allow for a stream of water. Lastly
enjoy the show!
Discussion
Working in a darkened room, begin by pointing out that the laser beam is monochromatic, or made up of one color. The
wavelength of the light determines the color we perceive. For a red helium-neon (HeNe) laser, the wavelength is 632.8
nanometers (nm). Red laser pointers typically emit at wavelengths of 635 or 650 nm. This represents a small part of the
visible spectrum. Explain that the human eye can detect wavelengths ranging from about 400nm (violet) to 700nm (red).
Point out that the light from the laser is directed. This means it travels in one direction and cannot be seen from angles
away from its direction of propagation. The light is there, but unless there is something reflecting it, we cannot see it.
Compare the laser light to the flashlight by shining them at a distant wall. The laser spot will be very small compared to
the area illuminated by the flashlight.
.
When light crosses into a new medium, some of the light will refract (bend) and some of it will reflect.
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Cow Eyeball Dissection*
Introduction
To explain the different structures and functions of a cow’s eye and how they are similar to that of a human eye.
Materials
• 3-4 Cow’s eyeballs
• Lab coat
• Gloves
• Scalpel
• Scissors
• Dissecting pan
Procedure
Wait for children to arrive in a group manner. Begin to explain the outside structure of the eye such as the cornea, optic
nerve, pupil, and sclera. Begin by cutting at the cornea until clear liquid (aqueous humor) below cornea is visible. We
explained to them that the clear liquid was the aqueous humor which helps keep the shape of the cornea and it is
composed of mostly water. Next, cut the eye in half and remove cornea to show where the iris and pupil are.
Then we removed the iris in one whole piece and exposed a hole in the center which is the pupil. Explain that the pupil
was the part of the eye that let light in and the iris contracts or expands to change the size of the pupil. When eye is cut in
half, the clear liquid in the back of eye (vitreous humor) is exposed. The vitreous humor is a mixture of protein and water,
which allows light to pass through and helps maintain the eyeball’s shape. Remove vitreous humor and lens, which is a
clear lump the size of a marble, from eye to expose the inside of the back of the eye. Some of the kids held the lens in the
palm of their hands. It was soft on the outside and hard in the middle. Inside the back of the eye, blood vessels and the
retina are visible. Retina is attached to the back of the eye at one spot. This one spot is the cow’s blind spot where all the
cells of the retina meet and go to the back of the eye forming the optic nerve. Under the retina, there is a shiny blue-green
material which is tapetum. Answer any questions that the children may have during the demonstration.
Discussion
Discuss with the kids the following questions:
1. How do you think a human eye and a cow eye are similar?
2. How do you think they are different?
3. What did you find interesting about a cow’s eye?
*Parental guidance required.
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Dry Ice Acidity Change
Introduction
Dry ice (frozen CO2) is added to a basic solution which contains a universal indicator. As the solution becomes more
acidic, it goes through several color changes.
Materials
• Several small pieces of dry ice (100 mL was needed for each beaker)
• Two 600mL beakers
• Two indicators (2mL was needed every time the experiment was performed)
• 3M Sodium hydroxide (NaOH) solution (2rnL was needed per performance)
• Distilled water
• 2 stirring sticks
• Waste container
• Gloves
Procedure
• Fill the beaker half way with distilled water
• Add enough universal indicator to give the solution a strong color
• While stirring the solution, add the sodium hydroxide until a very basic pH is attained
• Add a few chunks of dry ice to the solution
• Over the next few minutes, the indicator will undergo several color changes
Discussion
Sublimation is the process of going from a solid state directly to a gaseous state. When carbon dioxide gas is added to
water it forms carbonic acid:
CO2 (g) + H2O (l) � H2CO3 (aq)
As the carbonic acid is being produce, the pH of the solution is increases; therefore, causing the universal indicator to
change colors.
The solution was very basic, meaning it had a pH higher than 7 and when the dry ice dissolves in the solution, it lowers
the pH and changes the color of the indicators. A more sophisticated explanation is that the sodiurn hydroxide added to
the water made it an alkaline solution. When the solid carbon dioxide is added, the bubbles (which are carbon dioxide gas)
react with the water to form carbonic acid, and then this acid neutralizes the hydroxide ions to lower the pH, as observed
by the indicators.
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Magic Crystal ball
Introduction
This is a fun activity that uses dry ice, soap, and water to create a crystal ball to see the future.
Materials
• Bowls (large and/or small) with smooth rims
• Water
• 2 lbs. dry ice
• Gloves to handle dry ice
• 6 oz. of soap (no antibacterial or scented)
• Wash cloths or rags (one for each bowl)
Procedure
• Prepare a water and soap solution in one bowl
• Fill each of the remaining bowls half way with water
• With gloves on, add small pieces of dry ice to a bowl (not the soap solution)
• Note the vapor rising from the bowl as the carbon dioxide turns to a vapor
• Place a rag into the soap solution. Lightly ring out any excess liquid so that it’s not dripping wet
• Carefully place the rag at one end of the bowl and slide it to the other side of the bowl making a thin soap film
• The soap film will then begin to rise as the gaseous CO2 becomes trapped, making a crystal ball
• Try to make one solid bubble
• Once made watch the crystal ball form
• Once the frozen CO2 reacts with the water and the cover by a film of soap, the CO2 vapor is then trapped by the
soap solution that causes a bubble to form and the vapor can be seen from inside the bubble
• Eventually the bubble will pop due to the expand vapors inside the bubble.
Discussion
Sublimation is the process of going from a solid state directly to a gaseous state. As the dry ice started to sublime and
form gaseous CO2, the gas became entrapped by the soap film. This gas made the soap film expand until the pressure from
the gas became too strong and broke the bubble.
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Smoke Ring Vortex
Introduction
In this activity, we will generate smoke ring vortices using some household items and a smoke machine. The activity
show how smoke could be manipulated to form oscillating vortex rings.
Materials
• 2- 5 Gallon trash cans (plastic)
• Thick trash bags or 1 shower curtain
• Fog machine
• 1 Bungee cord or tape, very long
• 3 paint buckets
• POWER OUTLET
Procedure
• Cut an opening (approximately 3-6 inch diameter) at the base of the trash can. (Figure 1)
• Place the trash bag over the mouth of the trash can. Place the bungee cord around the trash
bag. If using tape, tape the bag down tightly. Make sure the bag is really taut. (Figure 2)
• Plug the fog machine into an outlet.
• Place the end of the fog machine (where the fog comes out) into the hole so that the fog can
accumulate in the trash can.
• Once the fog has accumulated, you can begin the demonstration.
• Tap the trash can at base where the trash bag is.
• A whirling smoke ring vortex should be ejected from the trash can.
Preparation for this experiment was quite simple. We set up our experiment on a standard table next to a power outlet for
the smoke machine. The first step was to fill the empty trashcan or paint bucket with smoke from the smoke machine.
Then we allow the students to tap on the shower curtain lined opening of the apparatus. From the impact on the shower
curtain we obtained pressurized air to disperse through the opening of the trashcan/paint bucket. This air oscillated upon
itself to create a vortex, which was highly contrast due to the smoke. The students were amazed at how perfect the shape
that the vortex produced. We explained the science behind this experiment by showing six PowerPoint slides which
showed slow motion captured photographs of how a vortex is formed.
Figure 1
Figure 2
Discussion
When one hits the base of the apparatus, the pressure displaces the fog content and it is ejected from the trash can. As the
“fog” moves forward it pushes air out of the way. Because air has friction, the moving fog will be stirred. The inside of
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the fog will spread apart and the outer layer is dragged backwards. A central stream of air moves through causing it to
swirl inside; consequently, the shape turns out to be donut-shaped.
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Seltzer Freeze
Introduction
The point of this activity is to instantly freeze carbonated water, in this case Club
Soda. Freezing point depression with carbonated club soda. Seltzer water was created by means of first adding carbon
dioxide gas into a bottle of water. It was then allowed to chill in an ice bath lower that the freezing point of water. It was
then removed from the ice bath after a few minutes and opened to release the carbon dioxide gas molecules and at that
point allowing the water molecules to expand and crystalize instantly into ice.
For the Seltzer freeze experiment I would suggest to pre-make bottles of seltzer water and placing them in the ice bath at
least forty-five minutes to an hour before conducting the experiment to the public. I did not have any pre-made bottles and
had to ask children to come back later because the water bottles could not reach the freezing temperature within a couple
of minutes. This disappointed some of the children and made me feel like I was not well prepared in the beginning of the
experiment. I attempted to show them that seltzer water can freeze instantly but the experiment continued to fail for the
first thirty minutes or so of our experiment presentation. Forty-five minutes into our presentations the experiment finally
worked because I had used one of the seltzer bottles placed in the ice bath at the beginning of the experiment. I also
suggest having better gloves equipped for handling ice because my hand burned and then went numb after having to deep
my hand so many times into the ice bath as I put in and took out seltzer bottles. In addition, paper towels are needed
because when we were trying to remove as much oxygen as possible from the bottles before adding carbon dioxide we
were spilling water all over our hands and on the floor so it was a bit messy and with the cold weather outside our hands
were freezing even more.
Materials
• 1 Carbon Dioxide Tank with Carbon Dioxide Regulator and hose
• 25 or more Mini Half-pint Bottled waters (8oz)
• 6 packs of carbonated seltzer water already pre-made and placed in the ice bath one hour prior to start
• 1 cooler
• 2-3 bags of ice
• Lots of rock salt
• 7-10 premade carbonation bottle caps with valves
• 3 rolls of paper towels
• 2 pairs of very thick gloves
• 1 table
• Thermometer
• Safety goggles
Procedure
• Peel any labels off the club soda bottle.
• Place the ice into the ice chests.
• Add sufficient rock salt into the chest with the ice.
• Submerge the unopened club soda into the salt/ice combo.
• Cool the bottle to a temperature of -10°C to -8°C. DO NOT cool past -10°C or the soda will freeze.
• Remove the bottle from the ice. Note that the club soda should still be in liquid form.
• Wipe off any condensation on the outside of bottle.
• Open the bottle.
• The soda should begin to immediately freeze, and be completely frozen within 30 seconds.
Discussion
A solution is a mixture of one substance dissolved in another. It is composed of a solute and solvent. The solvent is the
material in greater quantity and the solute is in the lesser quantity. A pure substance like water has a freezing point of 0°C
(32°F). When you add a solute to something such as water it reduces the temperature at the solvent freezes. This is known
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as freezing point depression which is a colligative property. In this demonstration for example, there is dissolved Carbon
Dioxide (CO2) in the water. Carbon Dioxide is the solute while water is the solvent. When CO2 was added to the water, it
reduced the freezing point of the mixture. This is why the club soda did not freeze when it was submerged in the ice.
When one opens the bottle, it allows the CO2 to escape; therefore, the only substance left in the bottle is water and the
freezing point of water is less than CO2; consequently, it instantly freezes.
An alternate explanation is that supercooling has occurred. Supercooling is the phenomena that a liquid surpasses
its freezing point and stays in liquid form. The reason behind this is, in a solid state the atoms align themselves in
an ordered structure. When the solution is supercooled, the molecules to not have enough time to structure
themselves and form a solid structure. The supercooled stage is very unstable; therefore, when one shakes the
supercooled solution it will begin to crystalize.
The first step in setting up for the Seltzer Freeze experiment was to create a very cold ice bath. Two to three bags of ice
were poured into a medium sized cooler. Then, half of a box of ice cream salt was poured over the ice within the cooler
and I used my hand while wearing gloves to mix it all very well. The purpose of the ice cream salt in the ice is for it to
lower the freezing point of water in our ice bath by making it colder that its current temperature. The freezing point of
water is 0°C (32°F) and our goal was to get our ice bath below this temperature as much as possible. Secondly, the
carbon dioxide tank was set up. The carbon dioxide regulator containing a hose was twisted onto the carbon dioxide tank
ensuring that it had a tight seal. Then, the pressure was set to 45 kPa. The experiment could now be started.
To prepare a water bottle first its original cap was removed and the bottle of water was squeezed slowly so that the water
level rose to the top of the opening of the water bottle top. Some of the water will spill and that is ok our goal is to remove
all of the oxygen within the bottle thus the carbonation bottle cap with a valve was twisted on quickly afterwards without
releasing your grip from the bottle of water. You bottle of water will now look as if all of the air was sucked out of it and
this is exactly what we want. This process removed all of the oxygen molecules within the bottle of water and it gave
room for the carbon dioxide gas that will be added next. At this point in the experiment I was asking children if they knew
what seltzer water was and I explained to them that it was bubbly water just like soda was bubbly. Next I showed them
how to make bubbly water by attaching and twisting on the hose from the carbon dioxide regulator onto the valve of the
carbonation cap on the bottle of water. Keep in mind that this end of the hose attached to the water bottle has a lever that
when pulled up creates a tight seal and when let down it is then able to be released from the valve on the carbonation cap.
Thus, ensure that the lever is down before twisting on the hose to your bottle of water cap and the lifting it. Next, the main
knob on the carbon dioxide regulator was slowly opened releasing carbon dioxide gas molecules into the bottle of water
until the bottom of the water bottle popped outwards. This indicated that the bottle of water was full and it contained its
full capacity of carbon dioxide molecules. Then, the lever was pushed down and the hose was unscrewed from the valve
on the cap. During this process I was asking the children if they knew the temperature at which water freezes? I informed
them that water froze at a temperature of 0°C (32°F). In order to make seltzer water freeze we had to place the water
bottles in an ice bath which we had made in our cooler. To the adults I explained that ice cream salt was mixed into the ice
to lower the freezing point of water. To the children I explained that rock salt in ice made the water freeze faster because it
was super cold like a freezer. Then, I inverted the water bottle a couple times before placing it in the ice bath for about 20
minutes. I then asked the children if they thought the water would be frozen just like when you put water in a freezer at
home. Then I took out premade seltzer water that had been in the ice bath for a while and showed it to everyone that the
water was not frozen within the water bottle. I further commented to everyone that once the bottle of water was removed
from the cooler you would assume that the water would have become frozen because it was at below water freezing
temperature, right? However, since carbon dioxide gas molecules (the gas in the bubbly water) created pressure within the
bottle by taking up all the free space in it and preventing the water molecules from expanding and crystalizing (becoming
ice) at the freezing temperature. Therefore, it was preventing the phase change from a liquid to a solid phase. Then I
asked the children if they wanted to see a magic trick on how to freeze seltzer water instantly. I explained to them that in
order for the seltzer water to freeze the carbon dioxide gas molecule and pressure from the bottle of water had to be set
free (released) from the seltzer bottle by removing the lid. Thus, I opened the water bottle in front of them and the water
froze instantly. Why? Because at that point the water molecules immediately had enough room to expand and also keep in
mind that since the bottle of water was kept at below the water freezing temperature it allowed the water molecules to
finally crystalize immediately creating frozen seltzer water right before their eyes. This experiment was repeated until
every child had the opportunity to see this experiment take place.
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Traffic Light
Introduction Demonstrate Oxidation-reduction (redox) reaction.
Materials
• 3- 125 mL Erlenmyer flasks
• 360 grams Dextrose
• 160 grams Potassium hydroxide (KOH)
• 4 Liters distilled water
• Indigo carmine indicator
Procedure
• Pouring 30 mL of the dextrose solution in the 125-mL Erlenmeyer flask
• Pour 30 mL of the potassium hydroxide solution in the same one the dextrose solution
• Then add enough of the indigo carmine to produce a rich yellow or green color
Discussion
The dextrose reduces the indigo carmine. The reduction part of the reaction is showed with the color change that occurred.
The air mixes with the solution and oxidizes the indigo carmine. A simpler way of explaining this is to say that an
oxidation reduction reaction occurs and that makes the color change happen that they were seeing in front of them.
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Elephant Toothpaste
Introduction
Demonstrate oxidation-reduction reaction with hydrogen peroxide and catalyst.
Materials
Kid-safe version Adult version 16 oz. Plastic soda bottle Hydrogen peroxide (30%) Over the counter hydrogen peroxide 2M Sodium Iodide Liquid soap Liquid soap Food coloring Food coloring 8 oz. yeast 500mL Graduated cylinder Foil cake pan with 2-inch sides Container to catch overflow Safety goggles Safety goggles Rubber gloves Rubber gloves Paper towels Paper towels
Procedure
There are two versions of this demonstration kid safe version and adult version.
“Kid safe version”
• Add 1 teaspoon of yeast to 2 tablespoons very water in a separate container. Stir and let sit for a few
minutes.
• Place the plastic bottle in the cake pan and pour approximately ½ cup of hydrogen peroxide into the cake
pan
• Add 2-3 squirts of dish soap to hydrogen peroxide.
• Quickly add the yeast mixture to the hydrogen peroxide solution.
• Foam will begin to shoot up and out of the bottle and into the pan.
• The kids can place their hands on the bottle to feel the change in temperature.
• Students can also play with the suds.
“Adult version”
• Have children stand back for this experiment.
• Dissolve 30 grams of sodium Iodide in 25mL of distilled water in a 100mL beaker. Add water to yield a
total volume of 100mL and mix well.
• Place the 500 graduated cylinder inside the plastic tub and pour 20 mL of 30% hydrogen peroxide. A
Discussion
The foam you made is special because each tiny foam bubble is filled with oxygen. The yeast acted as a catalyst (a helper)
to remove the oxygen from the hydrogen peroxide. Since it did this very fast, it created lots and lots of bubbles. Did you
notice the bottle got warm? Your experiment created a reaction called an Exothermic Reaction - that means it not only
created foam, it created heat! The foam produced is just water, soap, and oxygen so you can clean it up with a sponge and
pour any extra liquid left in the bottle down the drain. This experiment is sometimes called "Elephant's Toothpaste"
because it looks like toothpaste coming out of a tube, but don't get the foam in your mouth!
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Magic Pitcher
Introduction
Solutions of phenolphthalein, dilute sodium hydroxide, and vinegar are mixed resulting in the appearance and
disappearance of a pink color.
Materials
• opaque pitcher or beaker
• four 250 mL beakers
• phenolphthalein 1%solution
• vinegar
• M NaOH or household ammonia
• eye droppers or pipet
Procedure
• Label the 250 mL beakers 1 through 4.
• In beakers #1 and #3 add 30 drops of phenolphthalein 1%
• In beaker #4 add 45 drops of vinegar
• In the pitcher add 15 drops NaOH or ammonia and 400 mL water
Next….. explain to your audience that you have a pitcher that each time you pour from it you get a different solution.
• Pour 100 mL from the pitcher into each of the four beakers
o Beakers 1 and 3 will turn pink
o Beakers 2 and 4 will remain clear
• Pour beakers 1, 2 and 3 back into the pitcher- ask what the audience thinks the color in the pitcher is
• Pour 100 mL back into beakers 1, 2 and 3- they will all be pink
• Pour all 4 beakers back into pitcher, and then 100 mL back into the four beakers- they will all be clear
Discussion
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Glue Gak
Introduction
Making a solid gooey glue substance with Elmer’s glue and borax.
Materials
• 2- Large bottles of white Elmer’s glue
• 2-Large bottles of Tetraborate solution (4% solution)
• 8- Different colors of food coloring
• 1000 small sample cups
• 1000 Toothpicks
• Large box popsicle sticks
• Zip lock bags
• Hand wipes
Procedure
• In a sample cup squeeze a small, but good amount of glue into it.
• To the glue, add your choice of food coloring.
• Stir the glue and food coloring with a toothpick until no more white glue is visible.
• To the colored glue, while stirring rapidly with a popsicle stick, slowly add the borax until the glue starts
to solidify.
Discussion
The mixture of Elmer’s glue with borax solution produces a putty like substance called a polymer. Essentially what a
polymer is, is a chain of molecules
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Polyvinyl Alcohol Slime
Introduction
A solution of polyvinyl alcohol in water is mixed with laundry borax leading to the formation of slime.
Materials
• Sodium tetraborate 4% solution (4g borax in 100 mL of water)
• Polyvinyl alcohol solution
• Distilled water
• Beakers, 100 & 200 mL
• Stir Rod
• Food Coloring
• Hand wipes
• Neon green food coloring
Procedure
• Prepare the 4% polyvinyl alcohol (PVA) solution by dissolving 4 g polyvinyl alcohol in 100 mL distilled
water- the solution requires heating and stirring to fully dissolve- do not boil
• Once the alcohol has dissolved, food coloring can be added
• Add small amounts (1-2mL) of the borax solution to the polyvinyl alcohol solution, stirring continuously
Discussion
***Slime is not poisonous, but since it does contain small quantities of a toxic material (Borax) I would not advise leaving
it around unattended children.
The slime product behaves sometimes as a liquid and in other cases as a solid. Such behavior is called "viscoelasticity"
and materials are said to be "viscoelastic". Liquids can be poured and solids maintain their shape. How does this material
compare as a solid and/or a liquid?
The two types of solutions that are being used are polyvinyl alcohol and borax. Polyvinyl alcohol is a type of polymer. A
polymer is a mixture that has many molecules chained together to form a large chain. The borax is sodium containing
cleaning solution. When these two solutions are added together an interesting chemical reaction occurs. The borax will
create a cross linking to the chain of the polyvinyl alcohol and make the structure more tight. This tightness then will
make these two fluid solutions into a gel. The cross linking's are not held together very tightly so the constant mixing will
make the gel thicker. The basic steps to making it is having 4:1 ratio of the polyvinyl alcohol and borax. That makes 4 mL
of the polyvinyl alcohol and 1 mL of the borax. Put these two solutions together and add one drop of the neon green food
coloring into the solution. Stir it all together until the liquids turn into a thick gel like substance.
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15
Glowing Pickle DEMONSTRATION
Introduction
A large pickle is placed across the electrodes of an isolation transformer resulting in the pickle glowing from sparks
within the pickle.
Materials
• Large pickles
• Rubber Gloves
• 2 ring stands
• 2 utility clamps
• 2 forks or large nails
• 6 foot extension cord
• Electrical tape
• Power supply
Procedure
• First you want to set up the ring stands about a foot apart. Put the forks onto the ring stands with the
clamps, making sure the forks are facing each other. Now you want to put the pickle in position. Stick one
fork into the pickle - it is best to put all the teeth of the fork into the pickle, maybe even a little past is
great. Now stick the other fork into the pickle. BE CAREFUL THE FORKS ARE NOT TOUCHING
EACH OTHER - THEY WILL ARCH! I don't want to wear your pickle. Now with the variac off plug in
you extension cord into it and plug the variac in. With the variac power at zero turn on the switch and
SLOWLY turn up the voltage to 120 volts on the variac. (The standard voltage from a regular wall outlet)
• It will take a little while to start doing anything. The first sign that your pickle is doing something is that
you will see the pickle really start dripping. Then you''ll hear it start to hiss and see smoke coming out of
it. Then you should start to see it glowing shortly after that. Depending on how your forks are into the
pickle you may get the whole pickle to glow or just one half.
• You can shut the same pickle off and do it again if you like you can get at least 3 good glowings out of a
pickle - probably more, I haven't tried more. Oh! One thing I forgot to mention this little demonstration
REALLY SMELLS, so make sure you are doing it in a hood or can open a window
Discussion
When energy is added to electrons in an atom they give off visible light (in waves). Since each atom of an element is
different from element to element, the color of light that the electrons in that atom emit are different colors. Since there is
sodium in a pickle, in the form of table salt (NaCl), we can make a pickle glow. This is also how fireworks get their
colors - there are different salt that when the atoms are excited they emitted different colors. So when you see a green
fireworks the element giving that green color is copper (Cu). When you see a pink color that could be lithium (Li). Below
is a brief list of salts that I have gotten nice flame tests out of.
SALT COLOR OF FLAME
Soduim Chloride (NaCl) yellow / orange
Copper(II) Chloride (CuCl2) green
Lithium Chloride (LiCl) fushia
Calcium Chloride (CaCl2) orange
Strontium Chloride (SrCl2) red
Barium Chloride (BaCl2) yellow / green
Ok what does all this have to do with a glowing pickle??? Well what is in a pickle? Salt - NaCl. So if you add energy to
the sodium atoms in the pickle, the pickle will glow.
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Punch Carbonation/Cauldron
Introduction
Dry ice is added to punch leading to a bubbly cauldron of carbonated punch.
Materials
• Punch
• dry ice
• Cauldron for mixing (clear plastic dish?)
• Possible colored lights under cauldron
Procedure
• Dry ice is added to punch
Discussion:
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Glow Paintings
Introduction: Kids use glue to create a drawing which is then sprinkled with glow powder; the resulting art
created will glow in the dark.
Materials:
• 1500 sheets of black construction paper
• salt shakers
• 10 bottles of phosphorescent zinc sulfide
• Black light
• A lot of school glue
• Paper weight
Procedure:
• Use the glue to draw on the paper
• Using a salt shaker filled with phosphorescent zinc sulfide, sprinkle the powder over the paper
• Remove the excess powder
• Shine under a black light and your picture glows in the dark
Discussion:
The explanation for why the powder glowed in the dark after exposure to light was: the light excites the electrons out of
their ground state into a higher orbital, but when the light is removed the electrons move back to their ground state,
emitting energy in the form of visible light.
18
Screaming Balloons DEMONSTRATION
Introduction: A hex nut is placed in a balloon which leads to a loud noise as the balloon is twirled.
Materials:
• Clear latex balloons (9" to 11” and clear)
• 1/4" hex nuts
Procedure:
• Squeeze the hex nut through the mouth of the balloon making sure that the hex nut goes all the way into
the balloon so there is no danger of it being sucked out while blowing up the balloon.
• Then, blow up the balloon being careful not to overinflate the balloon. If overinflated, the balloon will
easily burst. Tie the end of the balloon.
• Grip the balloon at the stem end as you would a bowling ball. The neck of the balloon will be in your
palm and your fingers and thumb will extend down the sides of the balloon.
• Hold the balloon, palm down and begin swirling it in a circular motion. The hex nut will begin to spin and
making a screaming sound. Even when you stop swirling the balloon, the hex nut will continue to spin
for a few more seconds.
Discussion:
Centripetal force is the inward force on a body that causes it to move in a circular path. Since a hex nut has 6 flat edged
sides, it bounces or vibrates inside the balloon creating the screaming sound.
**For additional information, please refer to: http://www.stevespanglerscience.com/experiment/screaming-balloon,
http://www.youtube.com/watch?v=aAMW_3kWUhE
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20
Air-ball Bowling
Introduction: An air cannon is used to knock down plastic cups.
Materials:
• Megazooka
• Plastic cups
• Cardboard box
Procedure:
• Set-up the plastic cups in the cardboard box
• Let participants to use the megazooka to knock down cups in a cardboard box
Discussion:
Air occupies space. When the plastic membrane of the Megazooka is released, the volume decreases and pressure
increases. The increase in pressure forces some of the air out of the hole in the front of the megazooka. The velocity at
which the air leaves the Megazooka is inversely proportional to the diameter of the hole; the smaller the hole the greater
the velocity of the air. This is similar to the phenomenon when you pinch a garden hose to increase the velocity of the
water coming out the end.
***For additional information, see Edmund Scientific: http://www.scientificsonline.com/megazooka.html
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Mentos
Introduction
Mentos candies are placed in a 2L soda bottle leading to a jet of soda being blasted out of a hole in the lid.
Materials
• Mentos mint candies (1 entire case)
• 30 bottles of Diet Coke
• Mentos Mint Rocket Launchers (Dispenser) x4
*There were enough materials for the students to perform this experiment every twenty minutes.
Procedure
•
Discussion
This experiment demonstrates a basic interaction between the diet soda which has lots of fizzy bubbles and the porous
surface of the Mentos (even though it appears smooth) offers nucleation sites for the bubbles to interact with. The
interaction between the fizziness in the diet soda and the porosity of the candy causes lots of pressure to build up in the
bottle. A small hole was made in the top of the cap which allowed the soda to escape under high pressure high into the
sky. I also stressed the importance of wearing lab coats, gloves, and goggles while doing any experiment. Although Diet
Coke and Mentos are relatively harmless on their own there is always room for some error.
22
Liquid Nitrogen Effects (or Bouncy Ball Shatter, Balloon Shrink and Dragon's Breath
Introduction Various activities using liquid nitrogen to freeze bouncy balls, shrink balloons and freeze saltine crackers.
Materials
• Liquid nitrogen, one tank
• Saltine crackers, 8 boxes
• Balloons, 100
• Bouncy balls, 30
Procedure
• Inflate a balloon and submerge it in the liquid nitrogen
• Submerge a bouncy ball into the liquid nitrogen and try to bounce it; it will shatter
• Submerge a saltine cracker in liquid nitrogen; place the saltine in your mouth and breath out water vapor
Discussion
The bouncy ball shatter, can easily be described through the conversion of potential energy to kinetic. The reason for this
is because when you bounce a regular bouncy ball you take the potential energy of your dropping or throwing the ball on
the ground and convert it to kinetic energy when the ball uses its elasticity and compacts, then expands bouncing back up
off the ground. However, when you freeze the ball in liquid Nitrogen the molecules in the ball come closer together and
move around less, so when you drop or throw the ball the potential energy cannot be converted to kinetic, because the
molecules in the ball are already so close together and almost frozen, so that when the ball hits the ground it can't use its
elasticity to compact and then recoil, but instead the ball absorbs the energy and in turn shatters, causing a lot of
excitement with the kids as they cannot believe their eyes. The last experiment, Dragon's Breath, and the science behind it,
is explained by the composition of the air we breathe out. Because the air we breathe out consists of COz, Nitrogen and
water vapor, when submerged in liquid nitrogen to freeze a saltine cracker and place it in the mouth and breath out, the
temperature is simply cooling the water vapor and Nitrogen enough so that it is visible, causing it to look as if I am
blowing out smoke.
23
24
Multicolored Electrolysis
Introduction
A petri dish containing an acid-base indicator has electricity passed though it leading to swirls of color from one of the
electrodes.
Materials
• Petri dish
• Universal indicator
• Sodium sulfate solution
• 9 volt battery
• Neodymium magnet
• Electrode wires with alligator clips (preferable red and black)
• 2 pencils sharpened at both ends
Procedure
•
Discussion
25
Boo Bubbles (or Bizarre Bubbles) and Bubble Chamber
Introduction
Bubbles are generated using carbon dioxide from dry ice. When the bubbles pop they form a white cloud. Bubbles can
be held if wearing gloves.
Materials
• Bubble chamber made by Dr. Hampton (kiddy pool, ropes, hula hoop, PVC piping)
• Square bubble wand
• Extreme bubble solution (4 bottles)
• Dawn dish soap (-150 ounces)
• Glycerin (-l cup)
• Distilled water (-10 gallons)
• Mixing utensil
• 2 Hula hoops with handles attached
• Buckets and large containers to hold the bubbles solution
• Towels
• 10 pairs of cotton socks
• 2 Large filter flasks
• 2 Rubber tubings
• 2 Plastic funnels
• Dry Ice
• Food coloring
• Kettle
Extreme Bubble Solution
• 1 gallon DI water
• 12 oz. Dawn dish soap, classic
• 1 oz. glycerin
Procedure
Bubble Chamber
• The first part of our booth was a "bubble chamber, where kids could step on some bricks in a plastic pool
filled with bubble solution and then become encircled by a bubble. The solution, soap, water and glycerin
was supposed to sit for 24 hours before used it
• The bubble chamber is made by some PVC pipe, a hula hoop, and some rope
• Only allow the bubbles to go about halfway up the children before the bubble popped
• To set this up, you will need to create a rectangular prism out of the PVC pipe, attach the hula-hoop with
rope to the top of the contraption and create a pulley to bring the hula-hoop up around the child. Place the
pool on a level surface with a few bricks inside for the children to stand on. Pour the soapy bubble
solution into the pool. Have the child stand inside and pull the rope so the hulahoop surrounds them as it
rises. Hope for a day with no wind.
Boo Bubbles
• The second part of our booth was an activity called "Boo Bubbles"
• We put hot water and dry ice inside of a filter flask attached to a hose with a funnel and capped it tightly
with a rubber stopper
• We then dipped the funnel into a container of bubble solution (soap and water) and watched the bubbles
form with carbon dioxide inside of them. The oil and dirt on your hands is what typically causes bubbles
to pop, so by wearing cotton socks on their hands, the kids could hold the bubbles and watch them bounce
around
• As the bubbles pop, the carbon dioxide is released, creating smoke all around the table. These bubbles are
heavier, too because of the carbon dioxide gas inside mixed with the water vapor from the hot water.
26
Discussion
We discussed the hydrophilic and hydrophilic properties of the soap and water, and how surface tension plays a role. We
also discussed the desire for a bubble to have a low surface area which is why it automatically forms a sphere, the light
diffraction through the soap that causes a bubble to be so colorful and the hydrogen bonds made by glycerin that helps to
make stronger, longer lasting bubbles.
A bubble is a spherical mass of gas surrounded by a liquid or solid. The film that makes the bubble has three layers. A
thin layer of water is sandwiched between two layers of soap molecules. Each soap molecule is oriented so that its polar
{hydrophilic) head faces the water, while its hydrophobic hydrocarbon tail extends away from the water layer. Soap
bubbles are shaped by an equilibrium between their outward air pressure and the inward surface tension of the soap film.
No matter what shape a bubble has initially, it will try to become a sphere. The sphere is the shape that minimizes the
surface area of the structure, which makes it the shape that requires the least energy to achieve. Surface tension holds the
soap bubble molecules together while the air inside is forcing them apart. Colors are seen because of the light diffraction
through the soap film. Glycerln, C3H5(OH)3, extends the life of a bubble by forming hydrogen bonds with water, slowing
down its evaporation.
27
Telescope
Introduction
Telescope focused on Jupiter and the moon.
Materials
• Telescope
Procedure
• Have children look at Jupiter and the moon using the telescope with supervision.
Discussion
28
Bed of Nails DEMONSTRATION
Introduction
Lie down on a bed of nails with an apple between the nail bed and themselves. This is for us to demonstrate, not for any
of the guests to do.
Materials
• Bed of nails
• Apple
Procedure
• Lie down on a bed of nails, carefully
Discussion
29
Make Your Own Lotion
Introduction
Volunteers boiled solutions and measured out quantities, while students stirred and made their own lotion. Very hands on
activity. Some parents were concerned with the fact that their kids were touching “chemicals”. Some printed non-toxic
signs would help. Many parents did not get that many of these “acids” weren’t acids like hydrochloric acid, and some
parents felt unsafe. More people and more space is needed for the activity. A lot of stirring was required, and the kids
didn’t always want to stir. Thermometers are absolutely needed to maintain proper temperature of the water baths. More
stirrers were defiantly needed. Do NOT let the kids add their own scents. The kids jammed 10+ pipettes in the bottles and
created a huge mess. Have the parents add the scents.
Materials
• Stearic acid
• Cetyl alcohol
• Lanolin
• Triethanolamine
• Glycerol
• Water
• Pot
• Burner
• 2 digital thermometer
• 2 thermometer clamps
• 2 large (2000 mL or bigger needed) beakers for hot water bath
• 3+ clamps to hold tubes in water bath
• 4 sets of measuring spoons
• Ethanol
• Fragrance
• Little beakers for kids to take home
• Falcon tubes ~10 for boiling in the water bath
• Wood stir rods (do not use glass stir rods because the kids take them)
• Various scents
• Napkins
• Dropper bottles for the ethanol and triethanolamine
• Disposable pipettes
Procedure:
• Mix 3 g stearic acid, 1 g cetyl alcohol, 2 g lanolin and 1 mL triethanolamine together and heat to 80
degrees
• Mix 2 mL glycerol and 50 mL water together and heat to 80 degrees
• Mix both mixes together and add 5 mL ethanol and a few drops of fragrance
• Stir until thick
• Allow kids to put them in the beakers for them to take home
Discussion:
Discuss how one would set-up and conduct the activity including what scientific information one would convey to
students at various points in the activity.
Ingredients are mixed in the proper ratios (Dr. Deans has the recipe) and then melted in the water bath. Then the second
set of ingredients were melted and added into the little beaker given to the students. Ethanol was then added. Students
then stirred the mixture until it hardened, having the consistency of lotion. Then they added a few drops of the scents.
30
Students learned about the various organic acids, what an emulsifier was, and that science can be a little difficult. Do NOT
let the kids add their own scents. The kids jammed 10+ pipettes in the bottles and created a huge mess. Have the parents
add the scents.
31
Chemistry Rocket
Introduction
When you think of baking soda and vinegar, you probably think of two things: homemade volcano models or that gross
thing Aunt Muriel calls “dinner.” Don't let these lackluster and disgusting experiences put you off to the true potential of
this classic acid and base reaction. With the Chemistry Rocket experiment, you'll see just how explosive and exciting the
combination of baking soda and vinegar can be when it's in the right setting.
Materials
• 16 oz bottle
• Rubber stopper (needs to fit in opening of bottle)
• Tablespoon
• Baking soda
• Strong tape
• Scissors
• Three unused pencils
• Funnel
• White vinegar
• Paper towel
Procedure
• Using the scissors, (you've got to protect those pearly whites) cut a 12" piece of strong tape. Duct tape is going to
work the best, but you can substitute electrical or masking tape.
• Use the tape that you just cut to fix the three pencils to the outside of a 16 oz bottle. Try to keep the pencils as
equidistant from each other as possible. Your Chemistry Rocket needs to have a steady launch platform.
• Use a funnel to fill the 16 oz bottle halffull (or half-empty if your a pessimist) with white vinegar.
• Take a single paper towel from a roll. The paper towel you have is probably comprised of multiple layers, so
separate the paper towel until it is down to a single layer.
• Tear off about 1/4 of the paper towel and put one tablespoon of baking soda on the piece of paper towel.
• Wrap the baking soda in the piece of paper towel. Make sure that the paper towel can fit into the opening of the 16
oz bottle.
Now you're about to get a little (read: a lot) messy. You're going to want to take this experiment outside for the
rest of the steps. Trust us. Your parents and teachers will appreciate the thoughtfulness.
• This step has to happen quickly, or what you'll have is a failure to launch. Put the paper towel-wrapped baking
soda inside the bottle and immediately put the rubber stopper into the opening of the bottle. Give the rocket a
quick, hard shake and set it upright on the pencils. Stand back!
• You didn't really have time for a countdown, did you? You can do it now if you want… or you can just yell,
"Awesome!" and do the experiment again.
Discussion
What do you see when you mix baking soda with vinegar? You see a lot of bubbling. The bubbles that you see are
actually bubbles of carbon dioxide gas being released through an acid and base reaction. Vinegar contains acetic acid (the
reason it tastes so sour), and baking soda contains sodium bicarbonate (a base). Their reaction makes carbonic acid, an
unstable acid that quickly breaks down into carbon dioxide and water. The carbon dioxide then rapidly bubbles out of the
water.
When you close the 16 oz bottle with the rubber stopper, you prevent thegases from escaping the bottle, but you are
increasing the amount of gases inside the bottle by creating carbon dioxide. The introduction of carbon dioxide inside the
bottle causes a rapid increase in air pressure inside the bottle. The air pressure eventually gets to the point that the rubber
stopper can no longer contain the gases it holds inside the bottle and… WHOOOOOOSH!... the stopper and the contents
of the bottle rush downward.
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As the contents of the bottle rush downward, the bottle itself shoots upward. How does that happen? This is a fundamental
demonstration of Newton's Third Law of Motion: for every action, there is an equal and opposite reaction. The initial
action is the rush of matter and force downward from the bottle's opening. The reaction is the bottle jettisoning upward.
33
Flaming Dollar Bill
Introduction
By submerging a U.S dollar bill into a solution, we were able to light the dollar bill on fire without deteriorating it. For
the burning dollar experiment, I suggest correctly measuring the 3:1 ratio solution. If it is not correctly measure, chances
of actually burning the bill increase.
Materials
• One US dollar bill
• 30mL water *recommended 45mL
• 90mL 70% Isopropyl alcohol
• metal tongs
• lighter *recommended torch lighter
• 250mL beaker
Procedure
• Prepare a solution of a 3:1 ratio of 70% isopropyl alcohol and water, which is equivalent to 90mL of 70%
isopropyl alcohol and 30mL of water
• Stir the contents
• Using tongs, completely submerge the whole dollar bill in the solution (important: make sure the whole dollar
bill is wet)
• With tongs, take the bill out and set the beaker aside
• Light the bottom of the bill
• Allow the bill to burn (approx. 25 seconds)
• Once the flame has stopped, the dollar will be cool and ready to touch by the audience
Discussion
Would you like to see a dollar bill on fire? I am completely submerging the dollar bill in a 3:1 ratio of normal household
rubbing alcohol and water. Once it is all wet, I will light it and it will appear to catch on fire; however, the actual dollar
will not burn. The reasoning for this unexpected occurrence is due to the fact that the alcohol in the mixture has a high
vapor pressure. In other words, the temperature at which the alcohol burns is not high enough to evaporate the water.
When the dollar bill is lighted on fire, all of the alcohol burns away leaving only the water, which protects the dollar bill
from actually catching on fire.
34
Coin Color Change
Introduction
Copper pennies can be made to look completely silver and gold by adding a few chemicals and heating.
Materials
• clean pennies, don’t have to be pre-1982 pennies
• heating plate
• tweezers
• scoopula
• 100mL beaker
• 12 grams zinc metal (powder)
• 125mL 3M sodium hydroxide (liquid)
• 250mL water
• squirt bottle
• lighter
• evaporating dish
• bunsen burner
Procedure
Copper to silver pennies
• turn on heating mantel to medium heat
• with scoopula, pour 4g of zink powdered metal into evaporating dish
• add 25 mL 3M sodium hydroxide into dish
• place the dish on heating mantel and stir, then add about 5 pennies once mixture is hot
• with tweezers, flip and stir the pennies so that they are covered with the mixture
• after 5-7 minutes, pennies should turn silver
• remove the pennies with tweezers and use quirt bottle to wash and then dry the pennies
• add more pennies to the mixture and repeat
Silver to gold pennies
• hold one penny with tweezers
• using a lighter, heat and rotate penny until it becomes gold
• wash penny in water to remove any residue, then dry
Discussion
Would you like to see a penny turn silver or gold? By heating a mixture of powdered zinc metal and sodium hydroxide,
then adding pennies to it, we can make them turn silver. This is possible because zinc reacts with the sodium hydroxide
solution to form soluble zincate, which is converted into metallic zinc when it touches the surface of the penny. Since zinc
is a metal, it creates a thin covering film on the penny that appears silver. Then to turn the silver penny in to gold, I will
add heat to it by using a lighter. It can then appear gold because heating fuses the zinc and copper to form an alloy called
brass.
35
Gummy Bear DEMONSTRATION
Introduction
The Gummy Bear Sacrifice was meant to show kids that there is a lot of energy stored up inside sugar. Potassium chlorate
is melted to produce an excess of oxygen and when the Gummy Bear is added to the molten solution, the sugar in the
gummy bear reacts releasing all the stored energy as bright light. Drop two gummy bears into separate test tubes
containing melted potassium chlorate, causing them to burst into flames, give off smoke and make a whistling noise – all
in the name of entertainment and science!
Materials
• 30 Large Test Tubes
• Lab Coats
• 75g – 105g Potassium Chlorate
• Goggles
• 2 pairs of tongs
• Weigh boat
• Gloves
• 2 Bunsen Burners
• “Gummy Bear Sacrifice” Sign
• Lighter
• 2 People to Perform Demo
• 2 Tongs
• 2 Ring stands with their own clamp
• Test tube clamps
• Large bag of Gummy Bears
• 1500 plastic cups filled with gummy bears as giveaways
Procedure
Before the day of the carnival, measure out 6g potassium chlorate into a separate container to use as a reference amount
during the demonstration.
Set the two ring stands next to each other so the gummy bears can “race” once they’re dropped in the test tubes. It will be
beneficial to slightly angle the test tubes away from you so that the smoke and ash the demonstration produces goes away
from your face.
For the first demonstration, pour the pre-measured 6g of potassium chlorate into a test tube and make a mental note of the
amount so it can be duplicated in further tests, since you will be unable to measure the powder on site. Each test tube
should contain between 5g and 7g of potassium chlorate, but it doesn’t have to be precise.
While one partner uses the Bunsen burners to melt the potassium chlorate in both test tubes, the other partner should pass
out gummy bears to hold the crowd’s attention and ask questions such as:
“What are gummy bears made of?” (Sugar!)
“What happens when you eat a lot of sugar?” (You get hyper from the energy!)
Use the students’ simple understanding of energy to let them know that it is the sugars in the gummy bear which provide
the energy for the reaction.
Once the potassium chlorate is entirely molten, both partners count down and each use tongs to drop a gummy bear into
their test tube. The candy will burst into flames and make a loud noise for 10-15 seconds. When the flames die down,
explain what happened in simple terms, such as:
“When you melt potassium chlorate, it releases oxygen. The concentration of oxygen in the test tube was high enough to
react with the sugar in the gummy bear. There was so much energy in sugar that it made the big reaction you just saw
from one little gummy bear.”
-The Gummy Bear Sacrifice Demo was performed every 10-15 minutes with two gummy bears being sacrificed at once.
At the end of the night, only one gummy bear could be sacrificed at a time because we were running low on materials.
-To set everything up we had a test tube rack with two clamps facing opposite sides. The test tubes were secured tightly to
the clamps and the potassium Chlorate was added. Make sure the test tubes you are using are big enough so that the
gummy bear will fall to the bottom.
36
-The amount of potassium chlorate used was about 5g for every test tube. Weigh out 5 grams and use one of the test tubes
to estimate how much is needed for the rest of the trials. If two trials are running at once 120 grams of potassium chlorate
and 24 large test tubes will be needed if done in a 3 hour period. Have extra materials just in case! For our demo the
potassium chlorate was running low but we were only using the entire bottle of potassium chlorate so make sure you have
enough.
-Once the potassium chlorate has been transferred to the test tube begin heating up the bottom of the test tube with the
Bunsen burner or other source of flame. While one person heated up the tubes, the other volunteer can pass out gummy
bears to the audience. If you have a low supply of gummy bears make sure they only take one!
-When all of the potassium chlorate solid has melted you can add the gummy bear carefully with tongs and back away
once you release the gummy bear. Try to drop the gummy bear so that it does not touch the sides of the test tube. On more
than one occasion the gummy bear got stuck to the side of the test tube on the way down.
-After the reaction has completed and the smoke and lights die out, allow the test tube to cool down before discarding it.
This usually took around 6-7 minutes. We discarded every test tube as waste but they can be soaked and washed out with
water if you want to try and salavage the test tube. Check for any cracks in the tube afterward.
Discussion
Answer any remaining questions from students or parents once again, in a simple way that they can understand. When the
test tube has cooled down, dispose of it in a chemical waste bin, and set up the experiment so that you can run it again in
approximately 15 minutes.
While passing out the gummy bears and after the reaction occurs, talk with the audience about what is happening here.
Relate the experiment to how sugar gives people a lot of energy and all that energy released from sugar can be seen in this
reaction. If working with older kids, try to explain that this experiment was a combustion reaction in which oxygen made
all of the energy stored in sugar be released as heat and light. “Burning Sugars” from exercise can be related here as well.
37
Chemiluminescence DEMONSTRATION
Introduction
Materials
Supplies for synthesis
• Make TCPO
o 700mg 2,4,6-Trichlorophenol
o 10mL dry toluene
o 1mL triethylamine
o 0.3mL oxylchloride
• 15mL Ethyl Acetate (solvent)
• 1g Sodium Acetate
• 3mL of 30% Hydrogen Peroxide
• Fluorescing dyes
o 3-5mg 9,10-bis(phenylethynl)anthracene
Supplies for demo
Small vials to perform reactions, microwave
Supplies for Glow Stick Activity
3mg of 9,10-bis(phenyethynyl) anthracene
300mg of sodium acetate or sodium salicylate
10mL of ethyl acetate or diethyl phthalate
TCPO synthesized
3mL of hydrogen peroxide added last to initiate the reaction
Procedure
WARNING: When making TCPO, this process should be done in a hood, and using all lab safety gear, goggles, long
pants, lab coat and gloves. Certain stage when making this product hydrochloric gas can be present. The process is shown
below:
Take a small flash and add a stirring. Add 700mg 2,4,6-Trichlorophenol. Next add 10 mL of dry toluene, allow the
toluene to mix with the 2,4,6-Trichlorophenol for a couple minutes before continuing. Next add 1mL of triethylamine,
and allow the solution to sit and mix for a few minutes.
The next step does take patients. First take the flask with your sample in it, and put it on ice. Create a set up where the
stirring rod can still be able to mix. Although towards the end of this part of the synthesis the solution maybe too thick for
the magnetic stirring rod to work, and may need to be stirred with a spatula, be careful for any white gasses that may be
produce.
Once you have the flask on ice get a syringe and add 0.3mL of oxalyl chloride carefully. Adding oxalyl chloride should
almost be done drop wise. Once it is all added it may turn a brownish color, keep mixing it for a few more minutes on
nice, then allow it to warm up to room temperature. Next vacuum filter the sample. Allow it to vacuum filter for about 5
minutes to ensure the powder is dry. Next add 25 mL of methanol to your frits filter with the vacuum off. , Try stirring to
make the solvent and powder as homogenous as possible. Turn on the vacuum and let the white powder (TCPO) dry
completely. Allow the vacuum to stay on for 5-10 minutes.
In one glass vial or flask, added 700mg TCPO, 15mL of ethyl acetate, 1 gram of sodium acetate, 3-10 mg of one of the
listed fluorescent dyes. Once you’re ready to show the reaction add 3mL of 30% sodium hydroxide.
For a bigger batch upscale everything by a factor of 10, (I would not try to up scale making TCPO any further on 10
folds).
38
Increasing the volume of ethyl acetate added or adding 30mL of 3% sodium hydroxide can help increase the volume size
of the reaction and still get a successful reaction.
http://www.instructables.com/id/How-To-Make-TCPO-for-glow-sticks/
http://blog.makezine.com/2010/02/18/how-to-make-the-key-glowstick-chemi/
Dr. Lumos aka Chemoluminescence: demo manual, page 321 plus TCPO glow stick chemical experiment
http://www.youtube.com/watch?v=kH19EIf5GtE
To perform glow stick reaction mix these chemicals:
3mg of 9,10-bis(phenyethynyl) anthracene
300mg of sodium acetate or sodium salicylate
10mL of ethyl acetate or diethyl phthalate
TCPO synthesized
3mL of hydrogen peroxide added last to initiate the reaction
Discussion
This experiment can be applied to many standards, but the ones our group tried to direct our visitors to are the following:
• during chemical reactions the atoms in the reactants rearrange to form products with different properties.
• how to observe and describe similarities and differences in appearance.
• the properties of substances can change when the substances are mixed, cooled, or heated.
39
Self-Carving Hydrogen Pumpkin DEMONSTRATION
Introduction
The self-carving hydrogen pumpkin uses hydrogen gas and a spark to cause a chemical reaction inside a pumpkin, forcing
out the pumpkin pieces of a jack-o-lantern face with an accompanying loud bang.
Materials
• 8-10 pumpkins
• Pumpkin carving tools
• Hydrogen gas generator
o Two liters of 1M NaOH, prepared ahead of time (store labeled in plastic bottles)
o Aluminum foil
o Water bottle
o Tubing
o Parafilm
o Balloon
• Rubber stopper with a hole such that a BBQ sparker can be run through it and sealed with glue (can use the same
one from previous year)
• Another rubber stopper with no air holes
• Wooden kebab skewers
• Splash shields
Procedure
Preparation: A week before the carnival
• Prepare approximately 2 liters of 1 M NaOH
• Assemble the hydrogen generator according to Figure 1. A Gatorade bottle was used in this case. A hole was
created in the lid and tubing inserted down into the bottle. Parafilm was used to seal any leaks. On the other end
of the tubing, a balloon was attached using parafilm in order to contain the hydrogen gas while it is being
transferred to the pumpkin.
• Test your set up following the instructions below to figure out about how much hydrogen gas needs to be used to
get optimal exploding power. This will depend on the size of your pumpkins, but filling the balloon to about the
size of a softball should be sufficient. BE CAREFUL! Too much hydrogen gas will produce a very loud bang
and the face pieces can project a lot farther than you would expect!
• You will also need to determine how much aluminum needs to be added to produce the right amount of gas in the
allotted time period for demos, probably 15 minutes.
Preparation: Hours before the carnival
• Carve 8-10 pumpkins. Although some pumpkins may be able to be reused, a lot will be destroyed if too much
hydrogen is used and you do not want to be stuck carving a pumpkin during the demo.
• Don’t forget to carve 2 holes in the back side of each pumpkin for the insertion of the sparker and the tubing
which will allow for the hydrogen gas to get inside the pumpkin.
• Keep in mind that you may need to come early to do a demonstration for the fire marshal.
The demonstration: At the time of the carnival
Generating Hydrogen Gas
• Pour the 1 M NaOH into the bottle until it is about halfway full.
• Tear the aluminum foil into small strips and insert them into the bottle (the more you add the more gas will be
generated, and faster)
• Put the lid on the bottle and around the lid with parafilm so that the hydrogen gas fills into the attached balloon.
40
The Explosion
• Insert the BBQ sparker into the back of the pumpkin and ensure that it is still in working order. Try to minimize
leaks by ensuring that the hole is the same size as the stopper around the sparker.
• Make sure the face pieces and pumpkin lid are back in their original positions.
• Fasten the lid on the top with the wooden kebab skewers.
• When you have generated the appropriate amount of hydrogen gas, use the carving tools to cut around the lid of
the hydrogen generator so that it can be removed.
• Two people will be needed to transfer the gas from the balloon into the pumpkin. One person will need to create a
kink in the tubing so that the gas cannot escape during the transfer and the other will need to guide the end of the
tubing into the hole designated in the back of the pumpkin.
• Once the tubing is inside of the pumpkin, the next steps must be done as quickly as possible. Release the kink in
the tubing so that the hydrogen gas from inside the balloon is discharged into the center of the carved pumpkin.
• Remove the tube from the back of the pumpkin and seal the hole with a rubber stopper.
• Stand back and press the button to stimulate the spark that will induce the explosion.
Discussion
41
Colored Flames
Introduction
By igniting various salts in a methanol solution, you can send the electrons of the salts into excited states. When they
come back down, one will observe photons (light) in signature colors per salt.
Materials
2.5 liters Methanol
5 ½ liter spray bottles
5 Bunsen burners
25 g lithium chloride
25 g copper sulfate
25 g copper chloride
25 g potassium chloride
25 g magnesium sulfate
Procedure
Split the 25 students into groups of 5, each with a different salt, a spray gun, a Bunsen burner and ½ liter of methanol.
Each group will pour the methanol into the spray bottle, add the salt and shake to dissolve. Ignite the bunsen burner, and
then each student will take turns spraying the methanol solution into the bunsen burner.
Discussion
This experiment will demonstrate that putting energy into an atom (ignition) will elevate its electrons to a heightened
energy level for a short period of time. When the electrons come back down, they emit photons in the visible spectrum,
each a different specific wavelength relating to its chemical composition.
42
Acetylene Rockets – From Gemini to Saturn V
Introduction
This activity consisted of adding small pellets of calcium carbide (CaC2) to a tray of water, covering the pellets with a
plastic cup in order to capture the acetylene gas (C2H2 (g)) produced, and igniting the gas with a torch lighter through a
small hole that had been cut into the side of the cup before-hand. Upon ignition of the gasses, the cup would launch
several feet into the air, mimicking a rocket.
Materials
• 1 pizza tray with a raised lip around the edge in order to contain water
• 12 16 oz. plastic cups with holes cut/burned into them slightly above the water level to be used (12+ cups may or
may not be needed, some cups burst into flames and were deformed when they caught on fire)
• 1 torch lighter
• ~250g calcium carbide pellets (this should be plenty as it only takes a couple small pellets)
• 6+ bottles of water (more or less depending on number of times experiment will be performed)
• 1 waste bottle for liquid waste
• 1 funnel to make it easier to pour the liquid waste into the waste bottle
• 1 pair of goggles as water will splash
• 1 lab coat
Procedure
• Cut/burn small (1-2cm) holes into the plastic cups. The holes will need to be higher than the water level to be
used.
• Find a stable, level surface on which you will place the pizza tray. Proceed to fill the tray up with enough water to
create a shallow pool into which the calcium carbide pellets will be dropped.
• Immediately after you drop a few CaC2 pellets into the water, cover the resulting gas with a plastic cup. You
should not have to wait more than 2-3 seconds before enough gas is produced in order to launch the cup (times
will vary however depending on the size of the pellets and how many are used.)
• In most circumstances, the cup can be caught in the air as it falls back down and slammed back over the pellets in
order to capture more gas and produce another launch.
Discussion
The scientific information that students should be able to convey to students is the initial explanation that calcium carbide
is a water reactive substance. When it is introduced to water, it will produce flammable acetylene gas. It could also be
discussed that during combustion, carbon dioxide and water are produced.
43
Midway Carnival Games
Introduction
The Midway Carnival Games booth is to show the students how to apply scientific knowledge of projectiles and physics
to improve the chances of success with common Midway games offered at most carnivals. There were four activities set
up for the students to attempt including basketball toss, ring-the-bottle toss, quarter toss, and knock-over-the-pyramid.
Materials
Basketball Toss
2 small rubber basketballs
1 small plastic basketball hoop
Ring-the-Bottle Toss
25 glass soda bottles
1 box to hold the 25 glass soda bottles
6 plastic curtain rod hangers or similar circular object to throw toward the bottles
Quarter Toss
6 quarters
3 flat, circular ceramic dinner plates
Knock Over the Pyramid
6 stackable cups or bottles (preferably unbreakable since they will be knocked down repeatedly)
1 small ball to toss at the cups
These supplies were obtained with the student’s safety and ability level in mind. The supply list can be expanded for
larger groups of students, but the carnival had more than enough activities to offer that the kids did not have long to wait
to play the Midway games.
Procedure
***Make sure to have 1 person per table to explain the science behind the carnival game!!!
In order to set up the four activities that were performed at the carnival, one would first need to have an area large enough
for three 8-foot tables side-by-side and about a 15-foot distance behind one of the tables for the basketball hoop.
On the first table, the box of glass bottles can arranged so that the students have a clear shot at the tops with the plastic
rings. In order for the game to have an adequate level of difficulty, the students must stand about 5-8 feet from the table.
The goal is to throw the rings and land them around the top of the bottle. The scientific strategy to inform the students of
while they are attempting the activity is to throw the ring in such a way that the spin is stabilized and keeps the opening of
the ring perpendicular to the bottles. This throwing motion is much like throwing a Frisbee. The arch of the throw should
be relatively high, which will increase the chances of the ring dropping on a bottle. A lower-arched throw has a lower
chance of landing on a bottle. Also, a higher-arch throw has the opportunity to bounce off one bottle and onto another.
The student’s aim should be at the middle of the second row of bottles to give the greatest opportunity for success.
On the second table, a bottom row of three cups should be placed with the rims of the top touching. On top of these cups,
two more cups should be placed offsetting the bottom three cups. Finally, the last cup should be placed on top of the
second row of cups so that the six cups make a pyramid shape. The students should again be 5-8 feet behind the table.
The strategy for this activity is to aim for the top of the middle cup on the bottom row. This will take down the top three
cups and give a greater chance to knock over all six cups.
The third table is for the quarter toss. This can be performed by placing the three plates in a triangle shape with one plate
in front and two plates behind. The students then have six attempts to land a coin on one of the plates. This game has two
strategies: aiming to land the coin directly on a plate or bouncing off one plate onto another. The science of the throw is to
again use a high arch so if the coin bounces, it will ricochet and come down in close proximity to where it bounced. Also,
44
limiting the amount of spin on the coin will decreases the angle of ricochet and increase the chance of keeping the coin on
the plate. The goal is to get the coin to land flat on the plate.
The final activity is the basketball toss. It can be set up next to the tables. The students should stand about 15 feet from the
hoop and will be given two chances to make a shot. The strategy of this activity is to again use a high arching shot. At
most carnivals, the basketballs are usually hyper inflated and the backboard is usually very stiff. This causes the ball to
rebound off the hoop and decreases the likelihood of making the shot. For this reason, it is better to aim for the inside lip
of the rim instead of a bank-shot.
Discussion
45
Haunted Suitcase
Introduction
This activity illustrates inertia in the form of angular momentum. A suitcase is “charged” and the student is allowed to
walk with it. When the student changes direction suddenly the suitcase raises higher into the air. In order to demonstrate
this, a gyro was built inside a suitcase. Using an adaptor and a high speed electric drill, one can spin the bicycle wheel
inside the suitcase at relatively high speeds. Having two suitcases, one larger and one smaller, for varying sizes of kids
will be best.
Materials
Procedure
Discussion
While demonstrating the suitcase, one could talk about the physics behind the phenomenon that is the haunted suitcase.
Due to inertia, the suitcase will want to continue to travel in a straight plane. When the student suddenly deviates from this
plane, the suitcase will want to continue going in a straight line and resist the change. These forces can overcome those of
gravity and therefore, for a brief moment, the suitcase can “float” in mid-air. The inertia created is called angular
momentum. This is when an object such as a wheel spins and the inertia generated is a cross product of the moment of
inertia and angular velocity (I can draw this better). Angular momentum is conserved, and we can think of a figure skater
for this idea. When his/her arms are outstretched, the skater spins slower than when their arms are tucked in close.
46
PVC Marshmallow Shooter
Introduction
The marshmallow shooter activity involves a PVC designed contraption with an air inlet.
Materials
• 2 PVC Shooter
• 2 air compressors, commercial grade (60-70 PSI)
• Marshmallows
• Target
For 25 students it is best to have about 5 or 6 shooters and 2 people assisting each with separate air compressors. 2 people
are also needed in collecting the shot marshmallows. The air compressor must be commercial grade in order to fill the
shooters quickly and to the correct PSI (about 60-70). The marshmallows can be collected after shot and be reused.
Procedure
You need to gather the shooter air compressor and marshmallows. I also made a target this year and that can be used to
allow the kids to aim and attempt to score points.
Discussion
When filling up the shooters I would mention to the kids about pressure and how we are using air to shoot marsh mellows.
Another point one can bring up is the angle of the shooter and its corresponding distance.
47
Grain Silo DEMONSTRATION
Introduction
This demonstration show how surface area affects flammability of a substance, and relates it to a real world scenario.
Materials
• 1 Can with easily removable lid and a small hole at the bottom (we used a popcorn tin)
• 1 Medium sized funnel
• Small bits of cotton
• (I\ 4" x 4" mesh screen
• Rubber tube, large
• 1 Air pump
• 6 Tea light candles
• 1 Box matches or lighter (a long stemmed lighter would be preferable)
• 1 Ring stand
• 5 Salt/Pepper shakers
• 1 Folding table
• 50 grams of lycopodium powder
• Mesh screen
• Drill
• Drill bit (size depends on tubing O.D.)
• Clamp, small
Procedure
• The first thing to do is set up your ring stand
• Then place the popcorn tin on the stand, with the funnel inside. The funnel should protrude out the bottom of the
tin allowing for connection of the tubing to the funnel (this should also hold the funnel in place; a stabilizing arm
could be used here if needed).
• The cotton ball is then placed in the funnel. Take special care not to use too much. You want just enough to keep
the Lycopodium powder from falling into your tubing. Too much cotton will prevent enough air from dispersing
the powder.
• Next put about .5-l grams of powder in the funnel (we just used a watch glass to measure, about half a watch glass
full, NOT piled up).
• Next, your mesh screen is placed on the funnel, which acts as a platform for your lit candle.
• Place the lid on the popcorn tin, attach your air pump, and give it a shot of air
• The lid should blow off, with flames protruding, so you should make sure everyone is standing back a good
three or four feet
• The kids will want a hand in this, so we had candles laid out and let them use the salt/pepper shakers on the open
flame. lt creates a small fireball, but looks really neat. You definitely need to supervise the children when they
are doing this, and make sure they only give one shake at an angle, instead of multiple shakes from directly
above.
Discussion
The main premise of this whole experiment deals with surface area. Any fine grained organic molecule, when made
airborne, has a greater amount of surface area and transforms from a relatively non-flammable substance into an
extremely explosive one. Basically, when airborne, the fine particles become surrounded with oxygen instead of other
particles, and a combustion reaction takes place. For the actual grain elevators, this poses a great risk, so to avoid sparks
the grains are sifted to remove rocks and other debris, then magnets remove any other fine metallic debris. The vacuum
bomb is a good example of how dangerous this phenomenon can really be. According to Chemistry Daily, a vacuum
bomb works by utilizing two explosions. The first one propels explosives out of a container as a fine mist, while the
second charge detonates the mist. By allowing for the explosives to detonate as a mist rather than a canister, the damage
inflicted is much more devastating. This is made possible by the copious amounts of oxygen introduced into the system.
48
Instant Snow (or Plastic Snow)
Introduction
In this activity, kids make instant snow, which is a premade powder that when mixed with water will produce an enlarged
product that resembles snow.
Materials
• 2 beakers, large, glass
• Mini pipettes to draw small quantities of water out of the beakers
• Water
• Plastic cups, small
• Stirring rods, disposable
• Plastic bags, sealable
• 2 graduated cylinders with water
• Premade powder
Procedure
Prep
• Lay out the plastic cups and add a little bit of the premade powder (do trial and error to see how much of the
powder you should put in the cups)
• Fill up the beakers with water and put the mini pipettes next to each
• Fill up the graduated beakers with water (kids can use this instead of the beakers to see exactly how much water
they used)
Activity
• Allow the kids to pour water into a cup with the premade powder very quickly
• The snow will erupt out of the cup
• Kids can put the snow in a ziploc bag to take home with them
Discussion
The powder was a grained chemical compound commonly known as a polymer and when mixed with liquid water will
yield a product that looks like solid snow, but is not in fact snow.
49
Volcano of Doom DEMONSTRATION
Introduction
This activity was designed to wow young students through a simple acid base reaction with baking soda (sodium
bicarbonate) and vinegar (5oh acetic acid). The reaction causes a large pressurized plume of water, acetic acid, and soap,
propelled by carbon dioxide gas that travels roughly fifteen feet into the air.
Materials
For each demonstration, the following materials and amounts were used (have enough to do the demonstration at least 8
times at the carnival and 3 times to practice, for a total of 11 times)
• 4 volunteers
• 1/3 box of baking soda (1 ½ cup)
• 1 liter soda bottle and cap with a 3mm hole poked through the top
• Balloon
• 2 cups vinegar
• 1 tsp. of soap
• Coat hanger, metal
• Housing for the volcano (aesthetic value)
• 1 liter water
Procedure
• Before gathering your crowd, pre-load the empty soda bottle with a balloon containing two cups of vinegar
• Gather a crowd
• Have a volunteer fill the container with about 1.5 cups of baking soda
• Have another volunteer squeeze about a tsp. of soap into the bottle
• Have another volunteer fill the rest of the bottle with almost a liter of water leaving only a few inches of space at
the top
• Screw the cap on and tell the audience to stand back
• Place the bottle in the volcano housing
• Have the fourth volunteer puncture the balloon with a modified pointed coat hanger
Discussion
An acid base reaction between acetic acid (vinegar) and sodium bicarbonate (baking soda) will produce a product that
quickly dissociates into carbon dioxide, gas and water. The soap will aid in trapping this gas and the small opening will
cause a large amount of pressure to build and a huge eruption to occur.
50
Quirky Quicksand
Introduction
This activity is called Quirky Quicksand due to the different properties it could take on.
Materials
To make one batch of quicksand
• 1¼ cups of cornstarch
• ½ to ¾ cup of water
• Paper towels
• Hand wipes
• Measuring cups
• Spoons
• 3 bowls, large
Procedure
• Mix the cornstarch and water in a large bowl
• Mix it with your hands for the right consistency (add water or cornstarch as needed to get the right consistency)
• Place the 3 bowls out for people to see
• Use the cleaning supplies to clean the area and hands
Discussion
Ask the kids to try and touch the quicksand and ask them what they feel. Then, tell them to move their hand around the
bowl, smoothly and slowly. They concluded (and we confirmed) the mixture acts a liquid. It was then easier to move your
hand. Next, ask them to try and move their hand really fast or to try poking the bottom of the bowl. Again they could see
it was harder to move around in because the mixture was acting as a solid. They described it to us at times as being,
heavier, thicker and so on. So we concluded by explaining that this happened due to the fact that, the more force you place
on the mixture determines how solid the quicksand will turn; and how if you actually move slowly, you have a better
chance of getting out easily. It was determined that if you lie on your back, like you were in a pool, you would be able to
float to the top. This is because our bodies are less dense than the actual quicksand. We surprised a lot of people with that
fact.
51
Laser Pointer Maze
Introduction
The project is a reconfigurable maze of modular wall pieces made of Popsicle sticks and clay. The children set up small
hobby mirrors on popsicle stick stands in an attempt to bounce a laser-pointer beam into the maze's goal target. This
activity is rather difficult alone, so students should work in groups of 3 or 4, though pairs can work.
Materials
• 100 popsicle sticks
• Modeling clay, one box
• 30 one inch square hobby mirrors
• 4 laser pointers
• 2” picture of a target, a lot of them
***Have three students working in a group per maze, 25 students would require six mazes worth of materials.
Procedure
There are three basic pieces that must be made, the walls, the mirrors and the goal piece.
Maze Walls
• These are made by holding two Popsicle sticks together lengthwise, broad faces parallel
• Then balling up two clay pieces, stick them on the ends
• Press them lightly onto a flat surface to form post-ends that support the Popsicle sticks
Maze Mirrors
• Ball up a piece of clay, then roll the clay so it is a long, tubular piece almost the length of the Popsicle stick
• Place the clay along the broad face of a Popsicle stick
• Press a hobby mirrors into the clay piece, molding the clay around the mirror so it sticks to the Popsicle stick
base, keeping it as perpendicular as possible
Maze Goal/Target
• Prep: Find a picture of a target, print out many copies per page, try to get them about 2" wide, or as wide as a
popsicle stick. Cut these up into their squares
• Then place a balled and rolled piece of clay onto a popsicle stick base, press the target square into the clay, and
mold it so that it stays perpendicular
• The wall pieces and goal are arranged on a flat surface marked with borders in tape, pen, pencil, or just about
anything that limits placing mirrors within
Maze Set-up
• Place wall pieces in a configuration so that mirror stands must be used for the laser-pointer beam to bounce off
them to touch the goal
• The more reflections to hit, the harder it is (three or four mirrors was found to be the hardest a student could do;
parents could do more, but the time it took was not worthwhile)
• Keep the mazes modular and basic; the challenge of the activity can be entertaining but the precision required in
getting the mirrors to reflect the beam at both the right angle and right height can be frustrating and time-draining
without adding in objects that require solutions in the third dimension
Discussion
52
Make Your Own Root Beer
Introduction
Compressed carbon dioxide is admitted to a chilled water bottle to a pressure of approximately 40 - 50 psi resulting in
dissolution of the gas in the water and carbonation of the drink.
Materials
• Compressed carbon dioxide
• Chilled water bottles
• Plastic cups
• Root beer mix
Procedure
• Carbonate the water bottles and add the root beer mix.
• Pour in plastic cups and serve.
Discussion
53
Egg in a Bottle DEMONSTRATOIN
Introduction
A hard-boiled egg is placed over the opening of a flash into which a flaming, isopropanol soaked cotton ball is dropped;
as the flame extinguishes a vacuum is generated that pulls the egg into the flask. Heating of the flask with a hair dryer
causes the egg to come back out of the flask.
Materials
• Hard-boiled egg (NO SHELL)
• Glass bottle with an opening that the egg will not slip into
• Matches
• Cotton balls (soak with rubbing alcohol or ethanol before use)
• 100 mLbeaker
• Vinegar
• Baking soda
• Pie plate
Procedure
Directions to get the egg in the bottle
• Demonstrate that the egg will not fit into the bottle
• Light an alcohol soaked cotton ball on fire and drop the flaming cotton ball into the bottle
• QUICKLY place the egg on top of the bottle and watch the egg get pushed inside the bottle
Alternative: Is it really necessary to have a combustion reaction to make this demo work? For many years an erroneous
explanation cited that the egg went into the flask as a result of using up the oxygen. Less gas, less pressure, egg goes into
the bottle. In recent years, several articles have been published which state that this explanation is incorrect. Can we prove
it?
Is it necessary to have a combustion reaction to get the egg into the bottle? Heat the empty bottle on a hot plate for a short
time (several minutes), remove the bottle from the hot plate, place the egg on top of the bottle.
To get the egg out of the bottle
• Tip the bottle with the egg in it so that the egg lays near the opening of the bottle (try to aim the egg pointing
straight towards the opening of the bottle)
• Sprinkle about one teaspoon of baking soda all around the egg (especially on the sides)
• Pour in (or better use a large turkey baster) about 30 ml of vinegar, and quickly flip the bottle upside down with
the egg closing the opening above the pie plate. This procedure may take a little practice to get it down correctly
Alternative: With the egg in position, holding the bottle upside down, use a hair dryer to heat the bottle. This should force
the egg out of the bottle.
Discussion
The process of combustion (the alcohol burning inside the bottle) causes air inside of the bottle to heat up and expand.
Some of the original air is forced out of the bottle before the egg is placed on top. Before the egg is placed on top the air
pressure is the same inside and outside of the bottle. When the egg seals the top of the bottle, the flame goes out and the
gases on the inside of the bottle begiin to cool. The cooler molecules of gas, move less rapidly, causing less collisions of
the gas molecules, which results in less air pressure. However, the air pressure remains the same on the outside of the
54
bottle. This causes the air pressure on the outside of the bottle (which has a greater pressure than the inside of the bottle)
to push the egg through the tiny opening and into the bottle.
The reaction between the baking soda and vinegar produces the gas carbon dioxide. The pressure of the carbon dioxide
gas pushes the egg back out of the bottle. The gas is able to push the egg out of the bottle because there are now more gas
molecules, resulting in more collisions and a increase in air pressure.
Combustion:
alcohol + oxygen -----> carbon dioxide + water
C2H5OH + O2 ----> CO2 + H2O + heat
baking soda + vinegar -------> carbon dioxide + sodium acetate + water
Na(HCO3) + H(C2H3O2)-----> CO2 + Na (C2H3O2) +H2O
Safety: BE CAREFUL when you burn the cotton balls!!! Children should not do this experiment
55
Spinning Can DEMONSTRATION
Introduction
A soda can partially filled with water and having a hole on one side is heated over a butane torch resulting in a stream of
steam vapor exiting through the hole and causing the can to spin.
Materials
• unopened soda can or other small can
• ring stand with iron ring
• string
• fishing swivel
• straight pin or needle
• bunsen burner
Procedure
• Turn the opening tab around of an unopened soda can until it is on the opposite side from the scored opening.
Bend the handle portion of the tab upward at a 45 degree angle. Use this point to attach the can.
• Mark two holes on opposite sides of the can and approximately 2 cm from the bottom. Place the can in or near a
sink (remember – it still has soda in it). Poke a small hole at each of the two marks made on the can with a needle
or straight pin. The holes must be at tangent angles to the can, both in the same direction so that the escaping
steam jets can propel the can around in the opposite direction of the holes. However, make sure not to punch too
large of a hole; tiny openings will produce more steam thrust which, in turn, will spin the can faster.
• Next, drain the soda from the can by gently applying a slight pulsating squeeze to the can, so that soda is forced
out and air goes in. Do not squeeze so hard that the can bends or is creased. Alternatively, you can blow gently
into one of the holes.
• When the can is empty, attach a string to the tab on the can using a fishing swivel (any style or size). The swivel
will allow the can to spin without winding the string up.
• Add 1 to 1-1/2 cm of water to the can by lowering the bottom of it (containing the holes) into water and gently
squeezing and releasing, forcing air out and allow water in. Again, do not to squeeze so hard that the can is bent
or creased.
• Suspend the can by the string from a ring stand so that the bottom is a few centimeters above the flame on a
• bunsen burner. Ignite the burner.
• As the water begins to boil, water will begin to sputter out of the holes. As it comes to a full boil, steam will start
ejecting out of the holes and the can will begin to spin. If enough heat is applied the container can spin very fast.
Discussion
The Spinning Can demonstration is a valuable demonstration of steam power and gas laws (specifically, Charles Law: in a
fixed volume of a gas, temperature and pressure are directly related – as temperature increases, pressure increases
proportionately.
**For additional information, please refer to the Demonstration Manual, Bangs, Flashes, and Explosions –An Illustrated
Manual of Chemistry Demonstrations
56
Film Canister Pop (or Alcohol Jug Jet)
Introduction
Isopropanol is placed in a large polycarbonate water bottle and ignited with a spark source leading to a jet of flames
exiting the bottle and propelling a Nerf ball out of the mouth of the bottle. A parallel activity involves a spark source
within a film cannister igniting hair spray resulting in a "pop".
Materials
• Water container, 5 gallon
• Isopropyl
• Wooden matches
• Safety shield
Procedure
• Make sure that the 5 gallon water container does not have any hairline or spider fracture marks. DO NOT use the
container if there are any fracture marks. Find a new container! Do not use the container more than 15 times
for this activity. Bring more containers if you plan on doing the demonstration more than 15 times.
• Pour approximately 20-30 mL of isopropyl alcohol into the empty, dry jug. Turn the bottle on its side and roll it
slowly so that the sides of the container are coated, increasing the rate of vaporization.
• After approximately 1-2 minutes of rolling the container, drain any excess alcohol out of the jug into a sink.
• Place the container on a demonstration table behind the safety sheild and turn down the lights. Light a match and
quickly drop it into the jug. A loud whooshing sound and blue flame will be ejected from the container.
Discussion
Combustion of isopropyl alcohol proceeds as follows:
2 (CH3)2CHOH(g) + 9 O2(g) � 6 CO2(g) + 8 H2O(g) ⎝H = -1,235 kJ/mol
57
CSI at CI
***PARENT GUIDANCE REQUIRED
Introduction
Various activities related to crime scenes including making giant glowing fingerprint helium balloons and observing fake
blood stains using luminol.
Materials
Procedure
Discussion
58
Pig Lungs
Introduction
Pig lungs are inflated and deflated using a hand pump
Materials
Procedure
Discussion
59
Critter Microscopy
Introduction
Mosquito larvae, other interesting micro-organisms are observed using a microscope
Materials
• Micro-organisms
• Microscopes
Procedure
• Have children look at the micro-organisms through a microscope and have explanations prepared
Discussion
As needed
60
Rocks Rock
Introduction
Various rocks are displayed along with their properties
Materials
• Rocks
• Explanation of properties
Procedure
• Have students look at rocks
• Explain the properties of different rocks
Discussion
As needed
61
It’s Electrifying
Introduction
A van de Graaf generator and plasma globe are used to light neon bulbs and fluorescent light bulbs.
Materials
• Van de Graaf generator
• Plasma glove
• Neon bulbs
• Fluorescent light bulbs
Procedure
• Light neon bulbs and fluorescent light bulbs with a van de Graaf generator and plasma globe
Discussion
62
Adventures of Archaeology
Introduction
Students perform a dig for artifacts by sifting soil and analyzing what they found in the soil
Materials
• Artifacts
• Soil
• Boxes
• Digging tools, small
Procedure
• Fill boxes with soil. Hide artifacts in the boxes using the soil.
• Allow participants to dig through the boxes of soil to find artifacts. Return the artifacts so that new participants
have a chance to find them as well.
Discussion
63
Math Fun
Introduction
Mathematical curiosities with Dr. Cindy Wyles
Materials
Procedure
Discussion
64
The Physics of Sailing
Introduction
The CI Sailing Club teaches the physics behind sailing
Materials
Procedure
Discussion
65
Make Your Own Stress Ball
Introduction
Kids fill a balloon with sand using a vacuum chamber to inflate the balloon/ demonstrating how the lungs work.
Materials
• Handheld air compressors
• Inflation chamber/vacuum units
• Balloons
• Sand
• Funnel
Procedure
• Attach the balloon to the inflation chamber and use the pump to inflate the balloon
• Add your choice of filling to the inflated balloon (rice, flour, beads, etc.) and push relief valve to shrink balloon
over filled contents
Uninflated or broken balloons are a choking hazard to young children!!!
Discussion
**For further information, refer to Edmund Scientific: http://www.scientificsonline.com/stuff-it-balloon-filler.html
66
Amazing Feats of Fire: Cooking with Paper DEMONSTRATION
Introduction
A water-filled balloon and a cup filled with water are heated to boiling over a butane torch
Materials
• 100 Paper cups (small Dixie® cup)
• Candle or Bunsen burner
• Water
Procedure
• Place one empty paper cup on a ring stand over a Bunsen burner flame and the cup readily ignites
• Place a second paper cup that has been pre-filled with approximately ½ inch of water over the Bunsen burner and
the cup will not burn. After a short time the water begins to simmer, and then boil. The paper cup will not burn
until the water is evaporated off.
Discussion
Water has a high capacity to hold heat, and its temperature will not go above 100° C as long as it is a liquid. Water has a
heat of vaporization of 540 calories per gram (very high). Paper won't burn until its temperature reaches about 233° C.
The heat from the flame is absorbed through the paper into the water, which acts as a heatsink, and therefore prevents the
paper from burning.
67
Amazing Feats of Fire: Fireproof Balloon
Introduction
A balloon full of air is placed over a flame and it ignites; while, a balloon with water and air is placed over the same flame
and it does not ignite.
Materials
• 100 Balloons
• Bunsen burner
• Water
Procedure
• Blow up one balloon and tie the end.
• Then, fill a second balloon with approximately 1/3 full of water. Blow in some air and then tie the balloon as well.
• Hold the balloon filled only with air directly over the flame of the Bunsen burner. The balloon will burst.
• Hold the balloon with water directly over the flame of the Bunsen burner. The balloon will not burst as long as
there is water in the bottom.
Discussion
The balloon filled with only air bursts because the flame heats the rubber causing it to weaken. It eventually bursts due to
its inability to contain the higher pressure in the balloon. The water in the second balloon absorbs the heat and thereby
prevents the rubber from heating up enough to weaken. The water acts as a heat sink, absorbing the heat and conducting it
throughout the water.
**For further information, see http://scifun.chem.wisc.edu/HOMEEXPTS/FIREBALLOON.html
68
Sodium Alginate Gel Beads and Worms
Introduction
A solution of sodium alginate is added to calcium ions resulting in beads or worms, depending on the mode of mixture of
the two solutions
Materials
• Sodium alginate
• Calcium chloride
• Water (with low calcium content!)
• Blueberry syrup
• Water
• Blender
• Plastic syringe
• Steel cannula
• Bowl
Procedure
Mix the sodium alginate and water vigorously in a blender
Add blueberry syrup to the solution
Prepare a calcium chloride bath by dissolving calcium chloride in water. The sodium alginate/blueberry mixture was
dripped into the calcium chloride bath using a plastic syringe with a steel cannula. After 1-3 min the pearls were removed
and rinsed with water.
Discussion
Explore the science of building polymers by cross-linking long chains of molecules.
**For more information, see http://www.stevespanglerscience.com/product/small-clear-worm-goo-kit or
http://blog.khymos.org/2007/03/30/first-experiments-with-sodium-alginate/
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Tie-Dye Magic Markers
Introduction
Water-soluble magic markers are used to draw on filter paper and then the dye components separate as the filter paper is
placed in a glass containing water/ as the water wicks up the filter paper.
Materials
• Water
• Water-soluble magic markers
• Filter paper (or coffee filters), cut into strips that are at least 3 inches thick
• Clear, plastic cups
• Pencils
Procedure
• Have participants draw a relatively thick line on the coffee filter about an inch above the water's edge in one
color, using the water-soluble magic markers. The line should be about a centimeter thick. The line should stretch
from one end of the filter to the other.
• Participants tape the other end of the filter to a pencil. Tape it tightly so that when the chromatography is
complete and the coffee filter is soaked, the paper won’t tear off the pencil.
• Fill the cup with about half an inch of water.
• Place the coffee filter inside the cup, with the pen or pencil resting atop the cup. The end of the coffee filter
should be resting in the water at this point. If it is not, or if the mark on the filter is submerged, remove the coffee
filter, and fix the problem. Add more water if the filter was not touching the water, and, if the mark was
submerged, throw away that coffee filter, and try again, this time placing the mark higher on the paper.
• Remove the coffee filter from the cup when you think the colors have completely strained out. There should be
different colors moving in a long strip from the bottom of the filter up to the top.
Discussion
Chromatography allows us to pull and see all of the colors used to make different colors.
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Make Your Own Perfume
Introduction
Students combine various safe fragrant chemicals with ethanol to make their own perfume. Allergy warning. Make
sure to post that those with any possibly allergies should not participate.
Materials
• Perfume Oils
• Cotton Pads
• Flacons with Caps
• Atomizer
• Cap for Atomizer
• Dropper Pipettes
• Smell Strips
• Measuring Cups with Lids
• Stirrers
• Funnel
• Mini Flacons with Caps
• Perfume Bottle Label
• Pens
Procedure
Discussion
Learn how your nose and olfactory system work with your brain to sense and recognize smells.
For more information, please go to: http://www.scientificsonline.com/perfume-science-experiment-kit.html
71
Sugar Pyrotechnics
Introduction
A mixture of sugar and potassium chlorate is placed on a fireproof mat and a drop of concentrated sulfuric acid is added to
the mixture resulting in dramatic flames and smoke. A glass rod (magic wand) is touched to a small pile of white power,
ensuing in a reaction producing heat, violet flames, steam and smoke.
Materials
• Long glass rod (at least 40 cm)
• Potassium chlorate, KClO3, 9 g
• Sucrose (table sugar), C12H22O11, 18 g
• Sulfuric acid 18M, H2SO4
• Fireproof mat or dish
Alternate Reaction Materials
• Potassium permanganate, KMnO4, powdered, 5 gm
• Sucrose, C12H22O11, powdered, 5gm
• Fireproof mat or dish
• Dropper or beral pipet
Procedure
• Place a safety shield between demonstration and the audience.
• Mix the potassium chlorate with the sugar and pour into a pile on the fireproof mat or dish. For the reaction to
initiate properly the two powders need to be mixed thoroughly.
• Touch the glass rod to a small amount of concentrated sulfuric acid, so that there is a small drop on the tip of the
rod. Touch the rod to the top of the pile of potassium chlorate and sugar, carefully.
• The reaction will start slowly, but it will quickly increase in rate. As it increases in rate, heat, violet flames, smoke
and carbon will be released.
Discussion
When heated, potassium chlorate decomposes:
2 KClO3(s) → 2 KCl(s) + 3 O2(g)
This provides sufficient oxygen to ignite and oxidize the sugar in the gummy bear, which is an exothermic reaction:
C12H22O11(s) + 3 O2(g) → 9 C(s) + 3 CO2(g) + H2O(g ∆H = 5635 kJ
As the reaction proceeds, the potassium chlorate continues to decompose to oxygen and the rate of combustion rapidly
increases to a very rapid rate.
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Hydrogen Balloon Explosion DEMONSTRATION
Introduction
A balloon filled in a 2:1 ratio of hydrogen and oxygen gases has a small fuse attached with a piece of tape. When the fuse
is ignited, the balloon bursts with a flash of light and a loud report.
Materials
• Balloon
• Hydrogen source
• Meter stick with candle
Optional
• 6” Firecracker or cannon fuse (such as Visco safety fuse)
Procedure
• Make sure to place the balloon behind a safety shield and a good distance away from audience members and those
in the surrounding area.
• Ignite a balloon containing hydrogen using a candle attached to a meter stick.
• There will be a yellow flash and a very loud explosion.
Discussion
73
Butane Mamba
Introduction
Butane is bubbled into a soap mixture, producing a foamy column that slowly rises upward. When ignited, the column
gracefully combusts in a manner reminiscent of a Hollywood thriller.
Materials
Bubble machine
• 2 L plastic soda bottle
• Glass tubing approx. 10cm
• #3 1-hole rubber stopper,
• Bunsen burner hose
• Soap solution
• Barbeque lighter, or a candle secured to a meter stick
Soap Solution
• Dawn dish soap, 30 ml
• Distilled water to make 1 L
• Glycerin 5ml (optional)
Procedure
To make the Bubble Machine
• Cut a 2 L plastic soda bottle in half and discard the lower half.
• Run the glass tubing into the rubber stopper, adjusting the tubing so that it extends approximately 6 cm into the
bottle when the stopper is in place. Make sure the stopper is secured firmly into the bottle mouth so that the
bubble solution won’t leak.
• Attach the Bunsen burner tubing to the glass tubing tightly to avoid any leaking of the soap solution. If needed,
use an adapter or electrical tape to secure the connection.
• Place the soda bottle onto the ring stand with the mouth of the bottle with the rubber stopper secured firmly with
the utility clamp in such a manner as that the stopper is held tightly in place in the mouth of the bottle by the
clamp.
• Use an iron ring to hold the upper portion of the bottle in place. If possible, use a larger ring which is capable of
holding the wider portion of the bottle. This would be best; however, a smaller ring placed closer to the neck of
the bottle will work sufficiently also.
• Attach the rubber hose to the gas source making sure that the hose rises above the approximate level of bubble
solution that will be in the bottle in order to prevent backflow of solution when the gas is turned off. If necessary,
use a separate utility clamp or thermometer clamp for this.
• Fill the bottle with soap solution to a level approximately 2 cm above the glass tubing outlet.
Demonstration
• Make sure there are no open flames present.
• Turn the gas on full. A slow column of bubbles will grow out of the bottle.
• A column of bubbles will grow out of the bottle and rise upward. If the bubbles are too small the column will
curve downward.
Discussion
For additional information, please refer to: http://chemmovies.unl.edu/chemistry/beckerdemos/BD015.html
http://www.allatoms.com/methanemamba/mamba.htm
74
Eerie Green Glow
Introduction
Boric acid and methanol react in the presence of sulfuric acid resulting in trimethylborate which burns with a green flame.
A flask containing a small amount of a white liquid is shaken. When the lights are turned down and the bottle ignited, it
burns with an eerie, dancing green light.
Materials
• Boric acid, B(OH)3,10 g
• Methanol, CH3OH, 20 mL
• Florence flask, 1 L
• Ring stand
• Sulfuric Acid, H2SO4, conc., a few drops
• Parafilm® or stopper for the flask
Procedure
• To the flask add the boric acid, methanol, and a few drops of sulfuric acid.
• Cover the flask with parafilm or a rubber stopper and shake the flask for 40 to 50 seconds.
• Place the flask on the ring stand and turn down the lights.
• Light a match and uncover the flask to throw in the lit match. You will see a bright, dancing, green flame for
several seconds.
Discussion
Volatile boric acid trimethyl ester is produced: B(OH)3(s) + 3 CH3OH(l) → B(H3CO)3(l) + 3 H2O(l)
The boric acid ester and the excess methanol and atmospheric oxygen present are ignited. Boric acid ester burns with a
green flame.
For further information, please refer to: http://www.cci.ethz.ch/experiments/Borester/en/text/m.html
75
Fossil Booth
Introduction
Kids get to make their own cast of a fossil using plaster.
Materials
• Rubber molds (ammonite, crinoid, trilobite, cave bear tooth, shark tooth, and raptor claw)
• PerfectCast casting medium
• Background information on each fossil
• Paint
• Paintbrushes
Procedure
• Allow the kids to create the molds using the rubber molds and casting medium
• Have kids pain each fossil
• Have kids learn about each fossil
Discussion
Introduce the Earth's history in a thrilling fashion with authentic fossil replicas your students can actually take home!
For further information, please refer to: http://www.teachersource.com/product/fossilworks-fossil-molding-kit/biology-
life-science
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Jelly Marbles
Introduction
***This is for kids ages 6 and up! This may be a choking hazard for younger kids! Parents must be present!*** Polymer gel beads expand on exposure to water.
Materials
• Jelly Marbles
• True Colors Color Mixing Tablets
• Water
• Container for the water
• Mini-mixing tray
• Pipettes
• Plastic cups, clear
Procedure
• Have kids place one jelly marble sphere in a plastic cup with water
• The jelly marble will grow from 3 mm to 20 mm
• Use the color mixing tablets to create marbles that are different colors
Discussion
Polymers expand in water. These tiny spheres teach a big lesson in color, light and the importance of these thirsty
polymers can play in maintaining a healthy environment.
For further information, please refer to: http://www.stevespanglerscience.com/product/clear-spheres-kit
77
Magnesium Lantern DEMONSTRATION
Introduction
Magnesium turnings are ignited between two blocks of dry ice resulting in a dramatic display of light and smoke.
Materials
• Dry ice, 2 blocks per demonstration
• Magnesium ribbon, 6-8 cm
• Hammer
• Screwdriver or chisel
• Gloves
• Bunsen burner or propane torch
• Metal tongs
Procedure
• Put on gloves. Using the hammer and screwdriver, hollow out a small depression in the centers of each block of
dry ice. Make sure that the depressions are large enough to contain the loosely-coiled magnesium ribbon when
the blocks are placed together.
• Make sure the lights are dim. Light the end of the coiled magnesium ribbon using metal tongs and a Bunsen
burner or propane torch. Immediately place the ribbon into the well of one block of dry ice and place the other
block on top of the first, with the well covering the magnesium.
• The dry ice will glow brightly as the magnesium sparks and smokes.
• Remove the top block when the reaction is complete in order to reveal the pure carbon product in the well.
Discussion
When the magnesium strip was initially ignited in air, it underwent a synthesis reaction with oxygen to form magnesium
oxide: 2 Mg(s) + O2(g) → 2 MgO(s)
However, when placed between the two blocks of dry ice, it no longer had oxygen to react with. As the solid carbon
dioxide sublimed to a gas, a new reaction was initiated. In the presence of carbon dioxide, magnesium reacts violently to
produce carbon and magnesium oxide: 2 Mg(s) + CO2(g) → C(s) + 2 MgO(s)
78
Ruben’s Tube DEMONSTRATION
Introduction
A large PVC tube is filled with propane gas and music is played in one end leading to the formation of a standing wave of
flame across the tube. A Rubens' tube, also known as a standing wave flame tube, or simply flame tube, is an antique
physics apparatus for demonstrating acoustic standing waves in a tube.
Materials
• Ruben’s Tube
• Propane tank
• Lighter
• Speaker
Procedure
• Perforate a length of pipe along the top and then seal both ends. Attach one seal at the end of the pipe to a small
speaker or frequency generator. Attach the other sealed end of the pipe to a supply of propane. The pipe is filled
with the gas, and the gas leaking from the perforations is lit while the frequency generator is played or music
through the speaker.
Discussion
Invented by German physicist Heinrich Rubens in 1905, it shows the relationship between sound waves and sound
pressure.
For further information, please refer to: http://www.youtube.com/watch?v=haKcdjB_ns8&feature=fvwrel
79
DNA Extraction from Strawberries and Bananas
Introduction
DNA is extracted by blending a banana or strawberry and combining the mash with detergent and rubbing alcohol
Materials
For each child for strawberry DNA extraction
• Heavy duty ziploc bag (freezer or storage bag)
• 1 strawberry
• DNA extraction buffer (900mL water, 50mL dishwashing detergent, 2 teaspoons salt)
• Small plastic cup to hold extraction buffer
• Cheesecloth to fit in small funnel (4” X 4” should be appropriate)
• Small funnel
• 50mL vial / test tube
• Glass rod
• Inoculating loop, or popsicle stick
• Cold ethanol
• Ice
For each child for banana DNA extraction
• 1 large banana
• 3/4 cups distilled water
• 1 teaspoon clear, colorless (i.e., not cloudy) shampoo or liquid soap containing EDTA
• 1/4 teaspoon table salt
• 15 ml 91% isopropyl (i.e., rubbing alcohol) in 25 ml or 50 ml sealed test tube; chill the alcohol by placing the test
tube in a beaker containing ice cubes and some water
• Blender or smoothie maker
• 3 16-ounce plastic cups
• Tape (optional)
• 2 plastic spoons
• 1 set of measuring spoons and a measuring cup with 1/2-cup markings
• 1 #4 cone paper coffee filter
• 250 ml beaker
• 1 plastic pipette or medicine dropper
• 1 thin glass rod
Procedure
Strawberry DNA extraction
• In a container add 900mL water, then 50mL dishwashing detergent (or 100mL shampoo), and 2 teaspoons
• salt. Slowly invert the bottle to mix the extraction buffer.
• When the students add ethanol to their strawberry extract, they will see the fine white strands of DNA precipitate.
The DNA will form cotton like fibers that will spool onto the stirring rod/inoculating loop/popsicle stick.
Banana DNA Extraction
• Put 1/2 cup of distilled water and one banana into the blender. Blend for 25 seconds, making sure the banana is
completely pulverized. Pour the mixture into a beaker.
• Mix 1 teaspoon of soap with 1/4 teaspoon of salt in a plastic cup. Add 2 tablespoons of distilled water. Stir gently
to avoid creating a foam. Continue for a few minutes until the soap and salt are dissolved.
• Add 2 tablespoons of the banana mixture to the cup containing the soap solution. Use a spoon to stir the mixture
for at least 10 minutes.
• Insert a filter into a clean plastic cup so it does not touch the bottom of the cup. If necessary, tape the sides of the
filter to the cup.
80
• Pour the mixture from step 3 into the filter. After 10 minutes, some liquid, called the filtrate, should have
collected in the bottom of the cup. Gently stir the mixture in the filter and let it sit for another minute. Remove the
filter and set it aside.
• Get a test tube of cold alcohol. Use a pipette or eyedropper to collect your filtrate. Add it to the alcohol.
• Place the test tube with the alcohol and filtrate in a beaker or test tube holder. Let it sit undisturbed for about four
minutes. Do not shake. The white material coming out of solution as a precipitate is DNA.
• Dip the glass rod into the tube, slowly rotating it to spool out the banana’s DNA.
Discussion
Strawberry DNA extraction
Strawberries are soft and easy to pulverize. Strawberries have large genomes; they are octoploid, which means they have
eight of each type of chromosome in each cell. Thus, strawberries are an exceptional fruit to use in DNA extraction labs.
The soap helps to dissolve the phospholipid bilayers of the cell membrane and organelles. The salt is used to break up
protein chains that bind around the nucleic acids. DNA is not soluble in ethanol. The colder the ethanol, the less soluble
the DNA will be in it. Thus make sure to keep the ethanol in the freezer or on ice.
For additional information, please refer to:
http://gemsclub.org/yahoo_site_admin/assets/docs/StrawberryDNAExtra.4395135.pdf
Banana DNA Extraction
For something to be called living or alive, it must be able to reproduce. Cells are the functional units of living things. They
reproduce, in part, by making and passing deoxyribonucleic acid (DNA) from the parent cell to the offspring cell. All
DNA is made up of the same chemical bases, adenine, thymine, guanine, and cytosine. The order of the bases determines
the proteins the cell makes and the functions the cell performs.
In this activity, students extract DNA (and also some RNA) from bananas. They see that:
• DNA is a component of living and once-living things
• DNA can be extracted and observed
For additional information, please refer to: http://www.pbs.org/wgbh/nova/teachers/activities/pdf/3214_01_nsn_01.pdf
81
Colorful Gases DEMONSTRATION
Introduction
Gas discharge tubes are excited using a high voltage source leading to different colors of light being given off.
Materials
• High voltage source
• Tubes
• Gases
Procedure
• Use high voltage source to excite gases to have them give off different colors, according to the gas
Discussion
Gas-filled tubes exploit phenomena related to electric discharge in gases, operating by ionizing the gas with applied
voltage to start electrical conduction. Both hot cathode and cold cathode type devices are encountered. Depending on
application, either the glow from the gas or the electric arc or electric glow discharge may be the desired function.
For further information, please refer to: http://en.wikipedia.org/wiki/Gas-filled_tube
82
Dr. Glow & Dr. Lumos
Introduction
Fluorescent dyes are displayed under a black light to show the different colors of light given off, a solution of TCTO
(glow stick chemical) reacts with bleach, and luminol reacts with hydrogen peroxide.
Materials
Procedure
Discussion
83
Rocket Boys Rocket Launcher
Introduction
Students construct paper rockets, test rocket stability and launch with an air pressure rocket launcher.
Materials
• Paper (variety of weights-copy paper, construction paper, cardstock, etc.)
• Cellophane tape
• Scissors
• Rulers
• Pencils
• String
• Cardboard
• Modeling clay
• Rocket forms (short lengths of ½ “ PVC tubes)
• Fin and Nosecone patterns (Attachment #8)
• Posterboard
• Hot-Glue gun (to be used by teacher or adult volunteer)
• Launcher (See Attachment #9)
• Electric Air Compressor or Hand pump
• Safety glasses for the launch
Procedure
Safety Rules
• When pumping the launcher, do not exceed a pressure greater than half the rated pressure of the weakest part
noted on the PVC pipes’ and the valve’s pressure ratings. For example, if the lowest rating is 150 PSI, do not
pressurize the launcher to greater than 75 PSI. This provides a significant safety margin.
• Take care when handling the launcher as PVC can crack if dropped or struck with sufficient force. Make sure to
inspect the launcher before use. You will need to discard a launcher that shows signs of cracking.
• Do not lean over the launch rod at any time.
• Do not place anything inside the launch rod.
• Wear eye protection for launches.
Constructing the Paper Rocket
• Choose a type of paper and roll it around the short lengths of ½” PVC tube so that the tube serves as a form for
constructing the body of the rocket. Make sure that the paper is snug on the form, but still able to slide easily.
• Secure the paper roll using cellophane tape.
• Next, choose a fin shape and trace it on posterboard. Attach it to body of the rocket using tape (the fins should be
attached with hot glue after stability tests are completed).
• Trace nosecone, add modeling clay for weight if you wish, and attach to body of rocket with tape (he nosecone
should be attached with hot glue after the stability tests are completed).
• Perform rocket stability tests.
Perform Rocket Stability Tests
• Tie a string around the model rocket and adjust the string so that the rocket will be parallel to the floor in order to
find the center of mass on the rocket. Mark the line with a ruler.
• Spin the sample rocket in a circle using the attached string so that the nose cone will face forward without
wobbling. This is the swing test.
• To find the center of pressure, trace and cut out a cardboard silhouette of the rocket and balance this on a ruler to
estimate the center of pressure.
• After the three stability tests, you may want to make modifications before permanently attaching the nose
cones/fins.
84
Launch Procedure
• Select a clear field for the launch ensuring that the rocket does not injure anyone.
• Set up the launcher and orient the base so that the launch tube can point straight upward. Aim the angle of the
tubing slightly into the wind if it’s blowing.
• Connect the air compressor or hand pump to the tire valve on the launcher. Pump the launcher with up to 30
pounds of pressure with the valve closed.
• Test fire a rocket to see how far the rocket goes and in which direction. Make adjustments as needed to the aim
and pump the launcher up to 50 pounds of pressure. Again, test fire a rocket and make any final aiming
adjustments.
• Then, each student can load their rocket on the launch pad as long as they wear safety goggles. Making sure the
landing site is clear of bystanders, perform a countdown and launch the rocket.
Discussion
85
Title
Introduction
Materials
Procedure
Discussion
