Which Water Supercools Best?
Most recent answer: 01/14/2017
- Jessica (age 29)
Thedford, Ontario, Canada
Distilling removes molecular impurities in water, but the key nucleation sites to trigger ice forming are bigger particles, like little pieces of dust or bubbles. Flowing water is likely to have bubbles that trigger freezing, for the same reason that you can often trigger freezing in a supercooled bottle of water by shaking it.
Some bottled waters are filtered in ways that remove particles, so those are the easiest ones to supercool.
The release of heat when water freezes is very important in determining what happens to supercooled water. You can't supercool water enough for it all to freeze solid, because the released heat will warm it up to 0°C after part of it has frozen. That's why you get slush.
We discuss more here: https://van.physics.illinois.edu/qa/listing.php?id=1618.
Mike W.
(published on 01/14/2017)