| MadSci Network: Chemistry |
The phenomenon you describe is called "supercooling" and happens readily with water, especially very pure water. You can try this yourself -- Immerse a glass of distilled water into an ice/water slurry. Put a thermometer in the water and stir it vigorously. It is possible to supercool the water a few degrees. Then stop stir and the ice will rapidly freeze and the temperature will jump up. Supercooling happens more readily with pure water because impurities, especially small particles, can act as nucleation sites for ice crystallizatio
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