Dry Ice Lab

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Dry Ice Lab

• Kinetic theory and Phase Changes

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Warning!

• Dry Ice, if kept in confined areas, may cause an
  explosive rupture of its container

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Materials needed for all experiments

• Dry ice
• Film Canisters
• Blue Food coloring
• Karo Syrup
• Tongs
• Goggles

• Balloons
• Empty plastic water/soda bottles
• Straight pins
• Spoons

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Storing and Transporting Dry Ice

• Dry ice continuously sublimates as heat enters it
  from its surroundings.
• The CO2 gas that evolves must be vented from the
  container.
• Do not seal dry ice into a container except as
  detailed below, because an explosive bursting of
  the container can result.
• A Styrofoam (polystyrene foam) ice chest with a
  loose fitting lid makes a good container for
  transporting dry ice.

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Handling Dry Ice

• Due to its extremely cold temperature (-78.5oC,
  or -109.3oF), dry ice can cause damage to the
  skin if handled.
• Use tongs or insulating gloves when handling dry
  ice.
• It is also important when crushing or grinding
  the solid not to get any of the dust into your
  eyes.
• Wear protective goggles.

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To make a bubbling chemical mixture

• It's simple to create amazing effects using dry
  ice. At left is a plastic jar of water with blue
  food coloring and a piece of dry ice. 
• The thick blue substance at the bottom is clear
  Kraft Karo Syrup, which is denser than water,
  so it sinks to the bottom, encasing the dry ice. 
  
• As the dry ice sublimates, see below for
  definition of sublimation it creates
  interesting, mysterious blue bubbles in the syrup
  and water, along with fog spilling out over the
  jar.

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Popping film Cans

• A fun (and often wild) activity vividly
  demonstrates the sublimation process. Place a
  piece of dry ice into a plastic 35mm film
  container - the kind that has the snap - on cap.
  Then wait. The cap will pop off, and sometimes
  fly several meters. The clear Fuji brand
  containers shoot farther than the gray and black
  Kodak type. Warn anyone performing this
  experiment not to aim for anyone's eyes.

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Question

• Why does the top fly off
• Sublimation of the dry ice
• Creates increased gas pressure

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Blow up a balloon using dry ice!

• How could something as cold as dry ice blow up a
  balloon?

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Why does it do this?

• Remember that dry ice expands as into carbon
  dioxide gas when it sublimates. This experiment
  shows you how that works.

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What you need for this experiment

• Balloons with openings large enough to fit a
  plastic bottle opening
• Empty plastic soft drink bottle
• Small pieces or large pellets of dry ice
• Tongs to hold the dry ice
• Two people

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What to Do

1. Blow up one of the balloons and tie it off.
2. Save the balloon for later.
3. Remove the lid of the plastic bottle.
4. Have one person hold the plastic bottle upright.
5. Using tongs and wearing insulated gloves, take a
   few small pieces of dry ice and put them into the
   plastic bottle.
6. Fit a balloon over the opening of the bottle.
7. Watch the balloon inflate with carbon dioxide as
   the dry ice sublimates.
8. To make the balloon inflate faster, shake the
   bottle gently. Remember how we said that air
   currents make dry ice sublimate more quickly into
   carbon dioxide?
9. When the balloon is fully inflated, remove it
   from the bottle and tie it off.
10. Go and get the first balloon that you blew up
    with your own breath.
11. Toss up both balloons into the air.

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Notice how the balloon filled with carbon dioxide
gas falls quickly to the ground?

• Why?

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The answer

• That's because carbon dioxide is heavier than
  air.

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NextTouch the air filled balloon with a piece of
dry ice

• What do you think will happen?

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Steps/Precautions

• Wearing insulated gloves and using tongs, pick up
  a piece of dry ice and touch it to the balloon
  that you blew up with air not the one you filled
  with carbon dioxide.
• What happens to the balloon?

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Heros engine

• Using a push pin, or a straight pin held in
  pliers, poke two holes into opposite sides of a
  film can, near the bottom.
• The holes should be off - center, like pinwheel
  rockets. Tie a loop in a length of thread.
• The loop should fit loosely over the cap of the
  film can, so that when you loop it over the cap,
  and snap the cap onto the can, you can hold the
  can by the remaining length of thread.
• Place a small piece of dry ice into the can.
  Then quickly add some warm water, and close the
  lid, with the thread attached.
• Lift the can by the thread, and watch what
  happens.

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Heros engine
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Singing spoon

• Hold a warm spoon by its handle, and press it
  firmly against a chunk of dry ice.
• The spoon will scream loudly as the heat of the
  spoon causes the dry ice to instantly turn to gas
  where the two make contact.
• The pressure of this gas pushes the spoon away
  from the dry ice, and without contact, the dry
  ice stops sublimating.
• The spoon falls back into contact again, and the
  cycle repeats. This all happens so quickly that
  the spoon vibrates, causing the singing sound you
  hear.