minipost
Someone asked about the frozen bubbles we made years ago at Stony Brook. It turns out that bubbles freeze (there's some interesting physics going on) with interesting patterns.1 I've never tried to photograph them as (a) only about ten percent of my bubbles freeze properly and (b) I'm not a photographer.
The recipe I've used forever is
200 ml warm water (warm enough to dissolve the rest of the ingredients)
35 ml corn syrup
20 ml dish soap
25 grams (2 tbl white sugar)
a cold calm day or evening with some good lighting. I generally find temperatures between -15°C and -25° C best. One can experiment with the final water temperature as a first step. If you're really serious you could try a walk-in freezer. (not that I haven't been tempted)
Here's an excellent video on YouTube.
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1 Here's my hypothesis of what's going on. A liquid gives off a bit of heat when it freezes - the latent heat of fusion. Those vibrating water molecules lock into a structure and the energy of the water molecules motion has to go somewhere. When the bubble lands on a cold surface it begins to freeze at the point of contact. A ring shaped freezing front proceeds up the bubble. As the region freezes a bit of heat goes to the liquid part of the bubble in the immediate area that hasn't frozen causing a flow of slightly warmed water that moves upwards. This flow grows and puts stress on the freezing front causing bits of new ice to break off and slide around the still liquid part of the bubble. If I'm right the illusion that individual freezing zones form is just that - an illusion - and an artifact of the single moving ring.
The corn syrup gives sturdier bubbles.. the white sugar doesn't totally dissolve and gives good nucleation sites for crystal formation.
Of course this is just a guess that would need testing.
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