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Code Number: 4A40.30
Demo Title: Liquid Nitrogen - Ball, Rubber Tube, and Lettuce
Condition: Good
Principle: Material Properties at Low Temperatures
Area of Study: Chemistry and Physics
Equipment:
Liquid Nitrogen, Dewars, Rubber Hose, tennis ball innards.
Procedure:
See also: 4A40.30 in Chemistry and Physics of Everyday Experience
Arrange ahead of time to get liquid nitrogen from Biochem stores. Typically it takes about 4 liters for each classroom demonstration.
Dip the rubber hose into the nitrogen for a time and it will shatter like glass when struck against the lecture bench.
If you want to raise some eyebrows you can put a hot dog into one of the finger holes of a glove and then put the glove on. Dip your hand and the glove so that only the hot dog finger is submerged and then pull out your hand and hit it on the table breaking the hot dog and making people think you have just frozen and broken a finger.
Freeze the tennis ball innards and when thrown against the floor or wall it will shatter like glass.
Grapes when frozen will bounce much like steel ball bearings.
Lettuce and flowers may also be frozen in liquid nitrogen and when touched they will crumble like potato chips when you crush them.
The temperature of liquid nitrogen should be a -196o C or approximately 77o K.
A table of boiling points for some common liquids and gasses:
FLUID Boiling Pt. (K) Boiling Pt. (C)
Water 373 100
Propane 231.3 - 41.8
CO2 (sublimates) 194.6 - 78.6
Methane 111.6 - 161.6
Oxygen 98.2 - 183
Argon 87.3 - 185.8
Nitrogen 77.4 - 195.8
Neon 27.1 - 246.1
Hydrogen 20.3 - 252.9
Helium 4.2 - 268.9
Absolute Zero 0 - 273.1
References:
- Kathy Maline, Tejwant Datta, "Beware the Frozen Squash Ball", TPT, Vol. 32, # 6, Sept. 1994, p. 351.
- Floyd Holt and George Amann, "Cryogenics", TPT, Vol. 28, # 5, p. 321, May 1990.
- R. G. Hunt and G. L. Salinger, "Qualitative Demonstrations and Experiments Using Liquid Nitrogen", TPT, Vol. 7, # 5, May 1969, p. 289
- Hk-7, 8: Freier and Anderson, A Demonstration Handbook for Physics.
- H-078: "Objects in Liquid Nitrogen", DICK and RAE Physics Demo Notebook.
- Russell J. Hemley, George W. Crabtree, and Michelle V. Buchanan, "Materials In Extreme Environments", Physics Today, November 2009, p. 32.
- 50 Fun Experiments for the Mad Scientist in You, "Frozen Bounce", National Geographic Kids, p. 115.
- Julien Clinton Sprott, Physics Demonstrations, "2.9, Liquid Nitrogen", p. 88, ISBN 0-299-21580-6.
- Jearl Walker, "4.31, Dead-Cat Bomb and a Frozen Disappearance", The Flying Circus of Physics Ed. 2, p. 190.
- 10: "Liquid Nitrogen", Chemical Demonstrations, Vol. 2, pp. 20-21.
- Jeff Merritt, "Some Ideas for Demonstrations Using Nitrogen", PIRA News, Vol. 10, No 2, November 1995.
- Gordon McComb, Lasers, Ray Guns, & Light Cannons - Projects from the Wizard's Workbench, pp. 28.
- Borislaw Bilash II, “Cryogenic Malleability“, A Demo A Day – A Year of Physical Science Demonstrations, p. 30.