Do uncapped bottles change the outcome of freezing gas bubbles?

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SUMMARY

The discussion centers on a freezing experiment using commercial plastic mineral water bottles containing macroscopic gas bubbles. The experiment compares the effects of sealing versus uncapping the bottles on the preservation of these bubbles during freezing. It concludes that classical thermodynamics suggests that lower pressure in uncapped bottles may lead to different outcomes for gas bubbles, particularly those near the bottom, due to factors like gas absorption and ice expansion dynamics. The complexity of the interactions between temperature, pressure, and bubble integrity is emphasized.

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TL;DR
If macroscopic gas bubbles in mineral water survive freezing in a sealed plastic bottle — even under pressure from ice expansion —
should anything change when the bottle is left uncapped?
I’m repeating a simple freezing experiment using commercial plastic mineral water. The bottles contain pre-formed, macroscopic gas bubbles that remain perfectly spherical and adhered to the inner wall of the plastic.

When these bottles are sealed, freezing often preserves the bubbles intact, even under pressure from ice expansion.

I’m testing the same experiment with a bottle left uncapped.

Here’s the question:

If the pressure inside the bottle is lower (or at worst, equal) to ambient conditions, and if ice expansion was previously unable to crush or deform the bubbles under sealed pressure,
would classical thermodynamics predict any different outcome for the bubbles — specially those near the bottom of the bottle?

Attached: the first two images are from the previous experiment, the last is a microscopic comparison of the before and after freezing; the last image is what I'm testing now — it should not take long to be ready.
 

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I am not sure I buy into part of your premise.
As the water cools, the gas in the bubble will be more readily absorbed by the water.
Also, as the ice is forming, it would need to continue to flow as it expanded in order for it to change shape. Given the freedom to hold its shape, any cavities within the water would expand as the water/ice combination expanded. Of course, the plastic bottle will apply shape-changing forces to the ice/water mix. And decreasing temperatures also means that the gas pocket will tend to drop in pressure. So the situation is more complicated that it might seem at first glance.
 

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