Activity

Liquid nitrogen demonstrations

In this activity, students observe the teacher demonstrating changes in the properties of common substances when cooled with liquid nitrogen.

Spoon holding some Liquid Nitrogen

Liquid nitrogen.

Liquid nitrogen is a common laboratory coolant. With a boiling point of -196°C, it is cold enough to instantly freeze moist air in its vicinity. The ‘smoke’ is made up of tiny ice crystals.

Rights: Sascha Meinrath

By the end of this activity, students should be able to:

  • realise that the properties of materials are often temperature-sensitive

  • recognise that the boiling point of liquid nitrogen is extremely low

  • show awareness of the potential hazards that exposure to liquid nitrogen can invoke

  • explain in simple terms the reason behind the main changes occurring in each of the demonstrations.

Download the Word file (see link below) for:

  • introduction/background notes

  • instructions on what you need and what to do

  • discussion questions

  • ideas for extending your students.

Published:30 April 2010