4C20.40 • Phase Changes: Freezing Liquid Nitrogen

Photo of University of Texas at Austin's Demonstration

Instructions / Notes:

• Put about 20 ml of liquid nitrogen into a 100 ml beaker that is then placed in a vacuum chamber.
• Place the bell jar onto the vacuum chamber and evacuate the chamber until the LN2 freezes.
• Important Note: If you place more than 20 ml of LN2 into the beaker the demo will not work.

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Demo Staff:

• The valve is open when parallel to the spout and closed when perpendicular.

Last updated on December 3, 2025