Demonstrations
Liquid Nitrogen
Banana Hammer
Shrinking Balloons
Shattering Ball
Rubber Hose
Liquid Oxygen
Air Conditioner
Condensing Oxygen
Frozen Petals
Cloud Nine
Superconductivity
Dry Ice
Balloon
Bubbles in Aquarium
Magnesium Sparkler
pH Changes
Color Demonstrations
Rainbow Tube
Iodine Clock
Traffic Light
Blue Bottle
Luminol
Oscillating Reaction
Ammonia Fountain
Bad Breath
Fire / Explosive Demonstrations
Methanol Cannon
Polish Cannon
Gun Cotton
Lycopodium Powder
Methane Bubbles
Hydrogen Balloon
Hydrogen and Oxygen Balloon
Eggsplosion
Thermite
Barking Dogs
Flame Thrower
KMnO4 and Glycerin
Sugar, KClO3 and H2SO4
Zinc and Sulfur
Mini Fireworks
Pt Sparklers
Polymers
Slime
Silly Putty
Rubber Ball
Nylon
Water Lock
Miscellaneous
Memory Wire
Endothermic Reaction
Sodium Acetate Trees
Liquid Nitrogen Demos
Liquid nitrogen is a cryogenic liquid (of or related to low temperatures) and is stored at
77 Kelvin (-199ºC). The liquid boils at -196ºC. Since liquid nitrogen is so cold it has many uses
as a refrigerant (including keeping some electronic equipment cool and preserving simple living
organisms for long periods of time) and is also used to form inner atmospheres for the
preservation of other materials. Because of its cryogenic properties, the interaction of liquid
nitrogen with other materials can lead to reactions which are scientifically interesting, some of
which will be described in the following procedures.
Banana Hammer:
Place a ripe banana in liquid nitrogen. The nitrogen will boil rapidly, and then slow
down. At this point the banana is hard enough to hammer a nail into a small piece of wood. If
removed too early, the banana will be too soft to pound the nail, but if left in the liquid nitrogen
too long, it will be too brittle and will break. Note: Be sure to hold the frozen banana with a
cryo-glove.
Shrinking Balloons:
Have students blow up 5-7 balloons to a size slightly smaller than the opening of the
dewar containing liquid nitrogen. Place a balloon in liquid nitrogen. The balloon flattens as the
air condenses, allowing many more balloons to be placed into a small dewar.
Shattering Ball:
A racquetball is placed in a dewar of liquid nitrogen. After several minutes, the ball is
hard enough to shatter when "bounced." If the ball is removed from the liquid nitrogen too early,
it will bounce like a billiard ball. Note: Be sure to hold the ball with a cryo-glove.
Rubber Hose:
A small piece of rubber hose is placed in liquid nitrogen. Use tongs to remove the hose
from the liquid nitrogen. The frozen hose can now be shattered with a hammer.
Liquid Oxygen:
Carefully hold an oxygen filled balloon in liquid nitrogen (without tying). The oxygen
condenses inside the balloon. Quickly pour the liquid oxygen into a small Styrofoam cup.
Air Conditioner:
Put a small amount of water in an insulated cup. Add liquid nitrogen to the cup, and put
the lid in place. Water vapor pours out of the hole in the top of the lid, creating an "inexpensive
air-conditioner."
Condensing Oxygen:
Pour liquid nitrogen into a thin metal pan. Water vapor will instantly appear. Next,
liquid oxygen will begin to drip off of the pan. Collect the liquid oxygen in a test tube immersed
in liquid nitrogen (if the test tube is warm, the liquid oxygen will vaporize). Verify that the
liquid is oxygen by inserting a glowing splint into the test tube.
Frozen Petals:
Submerge a flower in liquid nitrogen until the liquid nitrogen no longer boils rapidly.
Remove the flower and crush it in your hand.
Cloud Nine:
Boil a large beaker full of water, and pour the boiling water into a large bucket. Pour
liquid nitrogen into the bucket, and a "cloud" instantly appears.
Superconductivity:
Cut off the bottom 2 cm of a Styrofoam cup. Place a super conducting ceramic disc in the
cup and place a small magnet on top of the disc. Pour liquid nitrogen in the bottom of the cup,
and the magnet will levitate. Touching lightly with a wood splint will make the magnet rotate.
Standards Met:
3.1.4.E – Recognize change in natural and physical systems.
 Describe the change to objects caused by heat, cold, light or chemicals.
3.4.4.A – Recognize basic concepts about the structure and properties of matter.
 Describe properties of matter (e.g., hardness, reactions to simple chemical tests).
 Know different material characteristics (e.g., texture, state of matter, solubility).
3.1.4.B – Know models as useful simplifications of objects or processes.
 Identify theories that serve as models (e.g., molecules).
3.2.7.B – Apply process knowledge to make and interpret observations.
 Describe relationships by making inferences and predictions.
3.7.7.A – Describe the safe and appropriate use of tools, materials and techniques to answer
questions and solve problems.
 Describe safe procedures for using tools and materials.
3.4.10.A – Explain concepts about the structure and properties of matter.
 Predict the behavior of gases.
Dry Ice Demos
Balloon:
Place a small piece of dry ice inside a balloon. The balloon will inflateas the dry ice
sublimes.
Bubbles in Aquarium:
Put several large pieces of dry ice in the bottom of a large aquarium. Blow soap bubbles
into the aquarium, and the bubbles will float. The bubbles will slowly expand and sink as the
carbon dioxide diffuses into the bubble.
Magnesium Sparkler:
Bore a small hole in a large piece of dry ice, and fill the hole with Mg powder, Mg
turnings, and KClO3. Use a piece of Mg ribbon as a fuse. Light the Mg ribbon, and a sparkling
effect occurs.
pH Changes:
Set up three large graduated cylinders. Fill the first two-thirds full of 0.1M NaOH. Fill
the second two-thirds full of tap water (check the pH of the water before using - it should be
neutral). Fill the third two-thirds full of 0.1M HCl. Add enough Fisher Universal Indicator to
each cylinder to make the liquids brightly colored. Add a small piece of dry ice to each cylinder.
The pH of the cylinders will become increasingly more acidic, as shown by the indicator.
Standards Met:
3.4.7.A – Describe concepts about the structure and properties of matter.
 Describe and conduct experiments that identify chemical and physical properties.
3.4.12.A – Apply concepts about the structure and properties of matter.
 Characterize and identify important classes of compounds (e.g., acids, bases, salts).
Color Demos
Rainbow Tube:
Fill a 50 mL buret two-thirds full of 0.1M HCl containing Universal Indicator. Add
approximately 1-2 mL of saturated Na2CO3 solution. A purple color will appear in the top of
the buret, and will slowly begin sinking toward the bottom. Place your finger over the top of the
buret and turn the buret upside down to create a rainbow of different pH. When the solution is
poured out of the buret into a beaker, it should be green. If it is not, add either HCl or Na2CO3
until the solution is neutral. It can then be poured down the drain.
Iodine Clock:
Prepare the following solutions:
Solution A - Add 4.3 g of KIO3 to 1 L of deionized water
Solution B - Make a paste of 4 g of soluble starch in a small amount of warm water. Slowly add
800 mL of boiling water. Boil for a few minutes, then cool the solution. Add 0.2 g of Na2S205
(sodium metabisulfite). Add 5 mL of 1.0M sulfuric acid. Dilute to 1 L.
Note: After the sulfuric acid is added to solution B, it must be used within 10-12 hours.
Put 50 mL of solution A in a 250 mL beaker. Put the same amount of solution B in a
second beaker. Mix the two solutions by pouring one beaker into the other. After a few seconds
the solution turns dark blue. This reaction can be timed and set up with several beakers that
change to dark blue as students count "one-chemistry, two-chemistry..." The time of the reaction
can be adjusted - just add a little more sodium metabisulfite or acid to solution B if the reaction is
too slow, or dilute solution A if the reaction is too fast.
Traffic Light:
Prepare the following solutions:
Solution A - Mix 3 g of dextrose (glucose) and 5 g of NaOH in 250 mL of deionized water.
indicator: 1% indigo carmine solution
Note: The solutions must be prepared fresh for best results.
Place 50 mL of solution A in a 250 mL flask. Add indicator solution until the solution is
a medium red color. Allow the solution to sit undisturbed and uncorked until the solution turns
yellow (this takes some time). Stopper the flask and swirl gently to produce a red color. Shake
the solution to produce a green color. Remove the stopper and allow the solution to return to the
yellow color before repeating.
Blue Bottle:
Prepare the following solutions:
Add 8 g of KOH to 300 mL of deionized water. Cool the solution and add 10 6 of glucose
(dextrose). Add a few drops of methylene blue indicator solution or a small amount (no bigger
than a match head) of the solid indicator.
Note: The solution must be prepared fresh for best results.
Put the solution in a stoppered flask. Shake vigorously, and the solution turns blue. After
a few seconds, the solution will turn colorless again (the solution may actually have a yellow
tint). This can be repeated, but it may be necessary to remove the stopper periodically.
Luminol:
Prepare the following solutions:
Solution A - Dilute 100 mL of bleach with distilled water to 1 L.
Solution B - Add 0.23 g of luminol to 500 mL of 0.10 M NaOH.
Mix A and B in equal proportions in a beaker to produce a glowing effect. An
interesting variation is to connect clear rubber tubing to the stem of a glass funnel and coil the
tubing around a ring stand using several utility clamps. Place the end of the tubing in a flask in
the sink. Pour solutions A and B from separate containers simultaneously into the funnel.
Oscillating Reaction:
Place a large beaker on a magnetic stirrer. Add 900 mL of water and 50 mL of
concentrated sulfuric acid. Use extreme caution when handling concentrated H2SO4. Place the
stir bar into the solution and begin to stir slowly. While the solution is stirring, add and dissolve
20 g of malonic acid, 20 g of KBrO3, and approximately 3 g of MnSO4 (exact amounts of these
are not necessary). The solution will fizz and turn brown. Oscillations will begin after a few
seconds.
Ammonia Fountain:
Set up the apparatus as shown in the above figure. Fill a large beaker 3/4 full with water
and add a few drops of phenolphthalein indicator.
To fill the flask with ammonia: place 7-8 g of ammonium chloride and 7-8 g of sodium
hydroxide in a large, dry test tube. Gently heat the tube in a hood and direct the ammonia
produced into the dry flask until the flask is full of ammonia gas. Alternative method: use a tank
of ammonia gas to fill the flask. Or place several mL of ammonium hydroxide in the flask and
heat. Pour out excess ammonium hydroxide.
Stopper the flask with a two-holed stopper fitted with a glass tube and a medicine dropper
containing water. Place the flask upside-down in the ring on a ring stand. Place the tube
extending from the flask in the beaker. The end of the tube should be just above the bottom of
the beaker. Remove the clamp, and begin the reaction by squirting water from the dropper into
the flask. A fountain will result as the water from the beaker is drawn into the flask.
Bad Breath:
Prepare the following solutions:
Saturated Ca(OH)2 - add 1 g of Ca(OH)2 solid into 500 mL of distilled water. Stir to dissolve as
much as possible, then filter to give a clear solution. Tightly cap this solution.
Phenol red indicator solution - place 0.1 g of phenol red in 26 mL of 0.01 M NaOH. Add 224
mL of water.
Bromothymol blue indicator solution - place 0.1 g of bromothymol blue in 16 mL of 0.01 M
NaOH. Add 234 mL of water.
Put 300 mL of the saturated Ca(OH)2 solution in flask A. Put 300 mL of water, 1 mL of
bromothymol blue indicator, and two drops of 6 M NH3(aq) in flask B. Put 300 mL of water, 1
mL of phenol red indicator, and 2 drops of 6 M NH3(aq) in flask C.
Have three volunteers breath through long straws into each of the three flasks. Flask A
will turn cloudy, flask B will change from blue to green to yellow, and flask C will change from
red to orange to yellow.
Standards Met:
3.4.7.A – Describe concepts about the structureand properties of matter.
 Describe and conduct experiments that identify chemical and physical properties.
3.1.4.E – Recognize changes in natural and physical systems.
 Describe the change to objects caused by heat, cold, light or chemicals.
3.4.4.A – Recognize basic concepts about the structure and properties of matter.
 Know that combining two or more substances can make new materials with different
properties.
Fire / Explosive Demos
Methanol Cannon:
Prepare the cannon by inserting two large nails through the sides of a heavy plastic bottle.
The points of the nails should be separated by about 1/4 inch to provide a gap. Use a piece of
copper wire attached to one nail to serve as a ground wire. Add about 1 mL of methanol to the
bottle, cork the bottle, then shake the bottle to vaporize and distribute the methanol. Empty the
cannon of any un-vaporized methanol. Connect the ground wire to a metal grounded object, i.e.,
a faucet or a ring stand. Point the cannon away from students, and use a Tesla coil to apply a
spark to the head of the nail that is not grounded. The result is a loud explosion, and the cork
will be propelled across the room.
Polish Cannon:
Prepare the cannon by cutting off the top and half of the bottom of one soda can. Cut the
top and the bottom half opposite to the first can off of a second can. Cut the top off of a third
can, and puncture a small hole in the side near the bottom (see figure below). Use duck tape to
fasten the cans together (put the first can at the top and the third can at the bottom). Tape the
mouths of two Styrofoam cups together - this serves as the projectile.
Put the Styrofoam cups in the top of the cannon, squirt 1-2 mL of 95% ethanol in the hole
in the bottom. Shake the cannon to vaporize the ethanol, and pour out any excess. Light the
cannon by holding a flame near the hole at the end of the cannon. Caution: The cannon will get
hot very rapidly after it is fired.
Gun Cotton (Cellulose Nitrate):
Place a 250 mL beaker in an ice bath, and add 70 mL of concentrated sulfuric acid (18M)
and 30 mL of concentrated nitric acid (16M) to the beaker. Divide the cotton into pieces of
approximately 0.7 g. With tongs, immerse each piece in the acid solution for 1 minute. Next,
rinse each piece in 250 mL of 1M NaHCO3. If substantial bubbling occurs, rinse the piece in
water once more and check for residual acid by immersing in the NaHCO3 solution. Squeeze dry
and spread on paper towels to dry overnight.
Hold a piece of the gun cotton with tongs. Light the cotton with the candle on a meter
stick, being careful that the cotton is not near anything that is extremely flammable.
Hazards:
1. Nitric acid and sulfuric acid are strong acids and powerful oxidizing agents, and can cause
severe burns. Spills should be neutralized with an appropriate agent (such as NaHCO3), and
then rinsed thoroughly.
2. Since the mixing of concentrated nitric acid and sulfuric acid evolves considerable heat, the
procedure must be carried out in an ice bath.
3. Gun cotton is extremely flammable and can explode if ignited in an enclosed space. If larger
amounts are used, use a longer holder for the candle.
Lycopodium Powder:
Hold some lycopodium powder in one hand, close to the fingertips. Put your hand close
to the flame and begin to release the powder to create a fine dust. As the powder catches on fire,
move your hand away from the flame, still releasing the powder. The powder itself is not
flammable, but like in grain fires, if it has a large enough surface area, it will ignite. The flame
will follow your hand as long as it has a large enough surface area. Caution: Do not swing your
hand toward your body or anything flammable.
Methane Bubbles:
Prepare a 3% Dawn solution. Cut off the top 6" of a 2 L soda bottle and stopper it with a
one-holed stopper fitted with a glass tube connected to a rubber hose. Clamp this to a ring stand
and fill it about 1/2 full with the 3% Dawn solution (make sure that the level of the solution is
above the glass tube). Connect the hose to a methane tank, and turn on the tank gently. Bubbles
will begin to form in the apparatus. The first bubbles that form will be mostly air. Remove these
and eventually methane will fill the bubbles. Collect the bubbles in one hand, and with your arm
fully extended, light the bubbles with a candle on a meter stick. Since methane is lighter than air,
the bubbles will burn upward, and only a small amount of heat will be felt. Caution: be sure
that the bubbles are only on the top of your hand, and that your arm is fully extended. Do not
pull your hand back toward your body or anything flammable after lighting the bubbles.
Hydrogen Balloon:
Fill a balloon with hydrogen and tie it closed. Use string to fasten the balloon to a heavy
object. Warn students to cover their ears, and then ignite the balloon using a candle on a meter
stick.
Hydrogen and Oxygen Balloon:
Fill a balloon with hydrogen and oxygen (two parts hydrogen, one part oxygen). Ignite
the balloon with a candle on a meter stick.
Caution: This explosion is extremely loud. It should be done outside and at a distance from
students. Students still may wish to cover their ears. The person igniting the balloon should
wear ear protection.
Eggsplosion:
Puncture both ends of a raw egg with a pin, and carefully blow out all of the egg contents.
Larger holes make it easier to blow out the insides, but be careful not to make them too large.
Fill a 6" test tube about 1/3 full of mossy zinc and add 6M HCl. Stopper the test tube
with a one-holed stopper fitted with a glass tube connected to rubber tubing. Put the other end of
the tubing inside the bottom of the egg after a few seconds. Tape the top hole closed and fill the
egg with hydrogen gas. After the egg is filled with hydrogen gas, set it upright in a 50 mL beaker
(taped hole at the top). Remove the tape and quickly hold a match near the top of the egg. After
a few seconds, the egg will explode. Caution: The explosion is quite loud, and egg pieces will
fly a short distance.
Thermite:
Obtain 2 clay flower pots, ca. 2 1/2 inch inside top diameter with 1 cm hole in bottom.
Place a piece of filter paper over the bottom opening of one of the clay pots. Put this clay pot
inside the other one. Mix 50-55 g of iron(III) oxide powder (Fe2O3) and 15 g aluminum powder,
(325 mesh or finer), and scoop the mixture into the pot. Form an indentation about 2 cm deep
and 1-2 cm wide in the center of the mixture. Fill the indentation with 20-25 g of potassium
permanganate crystals, and form another indentation in the center of this. Put the clay pots inside
a metal ring clamped to a ring stand. Place a heat-resistant pad under the ring stand, and a metal
bucket (ca. 20 cm in diameter and 20 cm deep) half full of sand under the clay pots.
Pour 5-6 mL of glycerin (glycerol - C3H5(OH)3) into a small beaker, and quickly pour
the glycerin onto the KMnO4 crystals. Stand back immediately. The mixture should ignite 1560 seconds after the addition of the glycerin. If the reaction does not ignite, wait 1-2 minutes,
and then add more KMnO4 and glycerin. If the reaction is successful, molten iron will run out of
the hole in the bottom of the pot into the bucket of sand.
Caution: If you have never done this demonstration, try it outdoors first. This demo
should only be done outdoors or in a well ventilated area, as it produces a large amount of
smoke. Sparks may fly 2 m vertically and 5 m horizontally. Keep all flammable materials away
from the experiment area. A fire extinguisher should be on hand during this demonstration. Do
not use water to extinguish the reaction. Do not use more than the recommended amounts.
Wear a safety shield throughout the demonstration.
Barking Dogs:
Cut a 4 g piece of white phosphorous (under water), and dissolve it completely in 20 mL
of carbon disulfide.
Lay a piece of filter paper over the top of a large graduated cylinder. Using a pipet, squirt
about 1-2 mL of the white phosphorous solution on the filter paper. When the carbon disulfide
evaporates (about a minute later), the filter paper catches on fire. The carbon disulfide vapors are
more dense then air, and thus, will settle into the cylinder. These vapors are also flammable, and
therefore will ignite inside the cylinder. This creates a sound similar to that of a barking dog.
Larger cylinders produce a lower pitch, while smaller cylinders produce a higher pitch.
Caution: This demonstration produces fumes, and should only be done under a hood.
Flame Thrower:
Clamp a test tube to a ring stand. Place KClO3 in the bottom 1/3 of the test tube. Heat
with a Bunsen burner until the KClO3 melts completely. Then insert any organic material (such
as a wood splint, a lifesaver, etc.) into the test tube to produce a flame thrower effect. Caution:
Stand back as you put the splint in the test tube, and quickly move your hand away from the
mouth of the test tube. Note that some of the organic material may be expelled from the test tube.
Be sure not to direct the test tube toward other people or anything flammable, since the flames
will be quite intense.
KMnO4 and Glycerin:
Place a small pile of granular potassium permanganate (about 10-15 g) in the center of an
evaporating dish. Add 10 drops of glycerin on top of the pile. Quickly stand back - the reaction
will occur in 15-20 seconds (just before the reaction begins, a slight puff of smoke forms in the
center of the pile). The reaction will produce a flame and intense heat. Dissolve the solid waste
in water and filter it. Flush the filtrate down the drain and place the precipitate in a solid waste
container. Caution: Do not add more than the specified amount of KMnO4, and only add
enough glycerin to wet the top of the pile. Perform under a hood or in a well ventilated room, as
a large amount of smoke is produced.
Sugar, KClO3 and H2SO4:
Mix 6 g of KClO3 and 2 g of granulated sugar. Pile the mixture on the base of a metal
ring stand, and put a small indentation in the center of the pile. Put 1 drop of concentrated
sulfuric acid in the indentation. The reaction will produce smoke within 2 seconds, and then the
pile will burst into flames. Caution: Handle concentrated sulfuric acid with care. Stand back
from the reaction quickly after adding the sulfuric acid.
Zinc and Sulfur:
Before beginning, place a combustion spoon on a tripod so that the handle is over a
Bunsen burner. Light the burner and adjust it so that the tip of the spoon's handle is in the hottest
part of the flame.
Mix 6 g of zinc and 1 g of sulfur to a homogeneous color. The mixing can be done on
filter paper with a spatula. Pile the zinc-sulfur mixture in the middle of the base of the ring
stand.
When the tip of the combustion spoon handle is red hot, quickly remove it from the flame
and place it in the center of the pile of powder. This must be done quickly, since the tip of the
wire must be as hot as possible. The reaction is violent, so the hands and body should be kept
away from the powder. Almost instantly, a brilliant flash of light, the emission of hot sparks, a
hissing sound, and a mushroom shaped cloud of smoke are produced. Note: this demonstration
should be performed in a well ventilated room.
Mini Fireworks:
Fill a 6" test tube about 1/3 full of concentrated H2SO4, and add about 5 mL of methanol.
Slowly drop a few crystals of KMnO4 into the test tube. A mini-sparkler effect results at the
interface of the two layers.
Pt Sparklers:
Cut two pieces of stainless steel about 6 cm and 15 cm long. Form a T with the two
pieces of stainless steel. This can be done either with epoxy, spot welding, crimping, or folding.
The T should be long enough to hang the Pt wire about 1-4 mm above the 150 mL line of a 500
mL Erlenmeyer flask. Flatten a piece of Pt wire with a hammer and attach it to the long end of
the T. The joint must be able to withstand heat from a Bunsen burner. Spot welding is
recommended, but tight crimping also works. Bend the Pt wire in an S-shape so it will fit inside
the flask and remain in a horizontal plane above the bottom of the flask. Pour about 150 mL of
methanol in the flask. The level should be about 1-4 mm below the Pt wire.
Hold the short end of the T and heat the Pt wire to glowing using a Bunsen burner. Be
sure to heat the entire Pt wire. Quickly put the wire in the flask, dropping the T in place. If done
properly, an immediate explosion will result. After the first explosion, the Pt wire will begin to
glow. If this does not occur, remove the wire while it is still warm and repeat the process. After
the wire glows for a short period of time, another explosion will occur. A pale blue flame will
burn inside the flask, and the Pt wire will appear to have "blown out." The Pt wire will heat up,
glow, and cause another explosion. This cycle will repeat for about 1/2 hour or longer.
Eventually, the Pt will no longer glow, which usually means that the methanol must be refilled
and the process must be started over. Caution: The demonstrator should wear goggles and
should stand back when putting the Pt wire into the flask, as the initial explosion can be quite
forceful.
Standards Met:
3.7.10.A – Identify and safely use a variety of tools, basic machines, materials and techniques to
solve problems and answer questions.
 Select and safely apply appropriate tools, materials and processes necessary to solve
complex problems.
3.4.7.A – Describe concepts about the structure and properties of matter.
 Describe and conduct experiments that identify chemical and physical properties.
3.4.4.B – Know basic energy types, sources and conversions.
 Know the characteristics of light(e.g., reflection, refraction, absorption) and use them to
produce heat, color or a virtual image.
Polymer Demos
Slime:
Prepare the following solutions:
Poly(vinyl alcohol) solution: Heat 1 L of distilled water to a temperature not to exceed 90ºC on a
stirring hot plate. Dissolve 40 g of poly(vinyl alcohol) in the water. Add a few drops of food
coloring (no scientific value - for aesthetic purposes only).
Borax solution: Dissolve 76 g of Na2B4O7 • 10H2O (sodium tetraborate or borax) in 1 L of
distilled water. Note: This solution is saturated, so it will take some heating to get all of the
borax to dissolve.
To make slime, mix the poly(vinyl alcohol) and borax in a 5:1 ratio [5 parts poly(vinyl
alcohol) to 1 part borax]. Stir with a stirring rod or a wood splint. The slime will be gooey at
first, but will then become more consistent as you continue to work with it. To preserve the
slime, keep it in an air-tight container while not in use.
Silly Putty:
Place about 50 mL of laundry starch in a 250 mL beaker. Add approximately 5 mL of
Elmer's glue and a pinch of salt. Mix until the glue sticks together. Remove the glue from the
starch, and then knead by hand until the consistency of silly putty is obtained.
Rubber Ball:
Pour about 20 mL of methanol into a small beaker, and add about 10 mL of sodium
silicate. Mix until the mixture is slightly more consistent than slime, then remove and knead into
a ball for approximately 10 minutes under running water.
Nylon 6-10:
Prepare the following solutions:
0.5 M hexamethylenediamine - Dissolve 3.0 g H2N(CH2)6NH2 plus 1.0 g NaOH in 50 mL
distilled water. Hexamethylenediamine can be dispensed by placing the reagent bottle in hot
water until sufficient solid has melted and can be decanted.
0.2 M sebacoyl chloride, ClCO(CH2)8COCl, in hexane - Dissolve 1.5 mL to 2.0 mL sebacoyl
chloride in 50 mL hexane.
Wearing gloves, place the hexamethylenediamine solution in a 250 mL beaker or
crystallizing dish. Slowly pour the sebacoyl chloride solution as a second layer on top of the
diamine solution, taking care to minimize agitation at the interface. With forceps, grasp the
polymer that forms at the interface of the two solutions and carefully pull it from the center of the
beaker. Wash the polymer with water or ethanol before handling. To make the layers more
visible, food coloring can be added.
Disposal: Mix together any remaining reagent to make nylon. Wash the solid nylon thoroughly
before putting it in the solid waste container. Any remaining liquid should be discarded in a
solvent waste container, or it can be neutralized and flushed down the drain with water.
Water Lock:
Pour 800 mL of distilled water into a beaker. The water may be colored with food
coloring, if desired. In another beaker, place 3 g of J-550 WATER LOCK™ powder. Pour the
colored water onto the WATER LOCK™, stir, and remove the stirring rod. A gelatinous mass
will instantly form. To "unlock" the bound water, sprinkle 5-10 g of NaCl onto the surface of the
gelatinous mass. Carefully mix and stir. The resulting fluid can be flushed down the drain with
water.
Standards Met:
3.4.4.A – Recognize basic concepts about the structure and properties of matter.
 Know different material characteristics (e.g., texture, state of matter, solubility).
 Describe properties of matter (e.g., hardness, reactions to simple chemical tests).
3.4.7.A – Describe concepts about the structure and properties of matter.
 Describe and conduct experiments that identify chemical and physical properties.
Miscellaneous Demos
Memory Metal:
Memory metal, or Nitinol, is a metal that can be bent into a new shape, and when placed
in a hot water bath, returns to its original shape. It has many commercial values, including its use
in switches to open or close vents that regulate hot air flow, but our use is merely as a
demonstration. To get more information or to obtain memory wire, write to the address below.
Institute for Chemical Education
Department of Chemistry
University of Wisconsin-Madison
1101 University Avenue
Madison, WI 53706
Endothermic Reaction:
Place approximately 20 g of barium hydroxide crystals [Ba(OH)2 • 8 H2O] in a 50 mL
beaker. Add 10 g of ammonium thiocyanate (or approximately 7 g of ammonium chloride) to the
beaker. Stir the two solids together with a wood splint. Place the beaker on a small, wooden
block with a small pool of water between the beaker and the block. After a few minutes, the
beaker will freeze to the block.
Sodium Acetate Trees:
Place 50 g of sodium acetate trihydrate in a small, very clean flask. Add 5 mL of water
and slowly warm the flask. Swirl the flask until the solid dissolves completely. Use a small
amount of water to wash down any solid remaining on the inside of the flask. Remove the flask
from the heat, wrap it in aluminum foil, and allow it to cool to room temperature. Be careful not
to agitate the solution.
Clean off an area in the lab. Place a few crystals of sodium acetate on the clean area, and
slowly drip the solution over the crystals. Crystallization begins and a tall column of crystals
forms.
Alternate method: fill a small, very clean Erlenmeyer flask with sodium acetate
trihydrate. Slowly heat the flask on a hot plate until it liquefies. Using a wash bottle, carefully
rinse the neck of the flask with a small amount of water. Stopper the flask and allow it to cool to
room temperature. After the flask has cooled, remove the stopper and add one crystal of sodium
acetate trihydrate to the flask. The solution will crystallize instantly.
Standards Met:
3.4.4.A - Recognize basic concepts about thestructure and properties of matter.
 Know different material characteristics (e.g., texture, state of matter, solubility).
3.7.7.A - Describe the safe and appropriate use of tools, materials and techniques to answer
questions and solve problems.
 Describe safe procedures for using tools and materials.