Learning Intentions
- To learn how water can get hotter than 100 °C or colder than 0 °C
- To learn the role of nucleation sites in phase transitions
Media
The transition from one state of matter to another is very complicated, and depends on lots of factors, including the material, the temperature, the pressure, and the container.
What is a Nucleation Site? How to Make Fewer Bubbles When You Pour Coke on Ice? (2:09)
The Danger of Boiling Water in the Microwave (0:38)
Superheating Water – Mythbusters (1:41)
Self Freezing Soda (3:17 – start at 0:33, end at 1:48)
Instant Freezing Popsicle (2:03)
Discussion Questions
- What is a nucleation site? How does this relate to crystal formation?
- Why does the water not boil, even though the temperature is above 100 °C?
- Why does the soda not boil, even though the temperature is below 0 °C?
- There is less air pressure on the top of Mount Everest than at sea level. Will water boil at 100 °C, less than 100 °C, or more than 100 °C? Why?
- What kitchen appliance uses pressure to increase the boiling temperature of water?