Liquid Nitrogen Show

Physics and Chemistry

States of Matter, Properties of Matter

Grade Range

Middle School, High School

Format

Stage Show

Materials

Note: This materials list pairs with the list on the Liquid Nitrogen page and the Meissner Effect page. Include the materials on the demonstration page with the ones listed below.

• Disposable rubber gloves
• Hot dog
• Red food dye (optional)
• Ball and Hoop
• Blowtorch
• Soap & water solution
• Half & half
• Heavy Whipping Cream
• Sugar
• Vanilla
• Ice Cream toppings
• Metal mixing bowl
• Whisk
• Disposable bowls and spoons

Demonstration

The Liquid Nitrogen Show is a full 45-minute show which presents the usual Liquid Nitrogen demonstration, the Meissner effect, and the following additional demonstrations:

Ball and Hoop

1. Show the Ball and Hoop to the audience, and how the ball currently cannot fit through the hoop.
2. Place the ball into the Liquid Nitrogen. While it is cooling, use the blowtorch to heat the hoop. Remind the audience of the Bimetallic plate, and how the metal expands and contracts slightly.
3. After heating the ball for at least 30 seconds, turn off the blowtorch. Quickly take the ball out of the liquid Nitrogen, and show that it now fits through the hoop!

Frozen Finger

Warning: This demonstration is a high risk demonstration, and has a high shock factor. Do not perform for any audience younger than 7th grade. Do not perform if you have never practiced it. Please follow all safety precautions with this demonstration.

Preparation: Before the show, take one of the gloves and a hot dog. Use the hot dog to fill at least one of the fingers, making sure to stuff it carefully so it isn't an obvious fake. If you want to go for maximum shock value, add 1-2 drops of food dye into each finger you fill. Set aside out of sight.

1. After presenting the Leidenfrost effect, put the rubber glove onto one hand. Do so carefully, and curl the finger(s) that are replaced into your palm. be careful not to show your palm to the audience, to keep the illusion up.
2. Slowly and dramatically insert the fake finger(s) into the liquid Nitrogen. Explain to your audience what is happening to your "finger(s)" as they freeze solid.
   1. This part requires careful timing to be done right. Do not stick any more than 1/2 of the fake finger(s) into the liquid nitrogen, or you will risk potentially serious injury to your hand. As the hot dog is freezing during this part, you will want to pay careful attention to what you feel. You will know that the hot dog is frozen either by careful timing (It takes about 15 seconds), or by feel; the hot dog might start to freeze to your knuckle if it is in too long.
3. When ready, pull the finger(s) out, and show how they are definitely frozen. Place your frozen finger(s) on the wood board, and proceed to shatter the finger(s) with the hammer.
4. Finish by showing that they were not your real fingers. Remove the glove to show that your hand is all right.

Exploding Soap Bubbles

Preparation: move the presentation thermos either into a large bin to catch overflow, or place on a tablecloth on the ground. If outdoors, place one the ground, making sure that students give it at least 10 ft of clearance. Make sure the presentation thermos is less than half filled.

1. Show the container with the soap and water solution to the audience. Explain the expansion rate of Nitrogen, from liquid to gas.
2. Have the students give you a countdown, and at the end of it dump about two cups of the solution into the liquid Nitrogen. There will be a dramatic explosion of bubbles!
3. After a couple of seconds, take the ladle and carefully scoop some of the bubbles that are still within the thermos out. They will be frozen!

Liquid Nitrogen Ice Cream

1. Mix the following ingredients together in the metal mixing bowl:
   1. 2 parts Half & half
   2. 2 parts Heavy whipping cream
   3. 1 part sugar
   4. 2-3 drops Vanilla for every 2 cups made
2. While one presenter mixes the ice cream batter, have the second presenter carefully pour the liquid Nitrogen in, with only small increments at a time. Be careful not to add too much of the LN2 at once!
3. After a few minutes, it will start to get solid chunks in it. continue to stir and pour slowly until you have a thick, chunky ice cream
4. Set out toppings for the ice cream, and enjoy!