Breadcrumb
4A40.45 - Liquid Nitrogen - Speed of Chemical Reactions

Code Number: 4A40.45
Demo Title: Liquid Nitrogen - Speed of Chemical Reactions
Condition: Excellent
Principle: Chemical reactivity at low temperatures.
Area of Study: Thermodynamics
Equipment:
Liquid Nitrogen in Dewar, Styrofoam transfer cup, 400 ml beaker, 9 volt battery with snap-on LED unit.
Procedure:
See also: 4A40.45 in Chemistry and Physics of Everyday Experience
Snap the LED unit onto the 9 volt battery. Place this into the clear beaker and fill the beaker with liquid nitrogen. As the battery cools the LED will become dimmer and will go out completely when the battery reaches liquid nitrogen temperature. The chemical reaction has now slowed to an extent where it is no longer able to light the LED. Remove the battery and LED unit from the liquid nitrogen and allow them to warm up. As the battery warms the LED will start to glow. The warmer the battery gets the brighter the LED will shine.
References:
- Axel Lorke, "Boiling Eggs, Radiation Damage, and the Arrhenius Plot", Physics Today, Vol. 74, #5, May 2021, p. 66.
- Janice VanCleave, "Speedy", Janice VanCleave's 203 Ice, Freezing, Frosty, Cool & Wild Experiments , p. 57.