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I am a Corporate Pilot and was in NY last week when the temperature was about -6 C. Our aircraft was parked for 36 hours and when I went back inside we had about 20 bottles (9 Oz.) of Evian water. I was amazed at how one of them was frozen solid and another one in a different location was not. The interesting thing to me was that after looking at the non frozen plastic bottle of water moments later it was now iced up but not completely frozen solid. I then started pulling other bottles that were in the ice chest out and they were not frozen either but one by one when I moved them I could see them change from crystal clear unfrozen water starting from the top of the bottle they would freeze up in front of me. They seemed to be affected by motion changing the water to ice. Do you have any idea what I was witnessing? Thanks Gary
- Gary (age 45)
W. Palm Beach Fl
Yes, we occasionally get variants on this same question. You can find
rather complete answers by searching this site with the keyword
'supercooled'. Your version is particularly nice because you see the
freezing without actually opening the bottles. Therefore we know that
reducing the pressure in the bottle is not part of your answer. The
water was cooled below its freezing point, but there was no ice nucleus
large enough to get the freezing started. Mechanical sloshing created
some nucleus to get things going.
(published on 10/22/2007)
Follow-up on this answer.