G460: Prep Notes

Introduction

Several pre-shrunk balloons are pulled from a single Dewar of liquid nitrogen and inflate back to their original size.


Supplies

Short List

  •   Balloons
  •   String
  •   Dewar containing liquid nitrogen
  •   tongs
  •   thick gloves

Prior to Lecture  (prep time ~ ? min.)

  1.        Blow balloons up and tie off.
  2. .      Tie string at top of balloon.
  3.        Shrink balloons by pouring liquid nitrogen over balloon in a Nalgene wash tray.
  4.        Transfer shrunken balloon to Dewar containing liquid nitrogen.
  5.        Assemble the following equipment:
  •   Balloons
  •   String
  •   Dewar containing liquid nitrogen
  •   tongs
  •   thick gloves

To Conduct Demonstration

  1. Using tongs and gloves, pull pre-shrunk balloons from the Dewar. They will inflate back to their regular size.

Reaction Time: 10 min

Safety and Disposal 

Take care when using liquid nitrogen to avoid prolonged contact with skin.