Submitted by The_Grand_Canyon t3_yy44ri in askscience
foundmyreddit t1_iwtbqbg wrote
I’m surprised no one has answered yet. Carbonation in soda is caused by the liquid being saturated in carbon dioxide gas. If the liquid freezes into a solid ice matrix then the gas will no longer be dissolved (solubility decreases as the liquid gets colder, and eventually once it becomes ice there’s no way for a gas to stay dissolved in a solid) and your soda will go flat.
I think this was the essence of your question — but it does get more complicated if you assume the container remains a closed system (ie the soda freezes but the bottle doesn’t explode). Then the gas will separate from the soda when it freezes but will stay trapped in the bottle. Once the soda is thawed back into a liquid, some of the trapped gas will likely go back into solution, but it’s unlikely it’ll be as carbonated as before freezing
magnets_are_strange t1_iwtgg22 wrote
Just want to add that the solubility of gases in a liquid actually increases with decreasing temperature. But regardless, everything else you said is essentially correct.
foundmyreddit t1_iwtgsqt wrote
Oop, I always forget that it’s opposite for dissolved gasses as for dissolved solids/liquids, but yes you’re right!
Twink_Ass_Bitch t1_iwthnkn wrote
Also, it's generally the case that solubility of solid solutes increases with temperature, but it depends on the substance.
[deleted] t1_iwti9gn wrote
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asteconn t1_iwtuqzb wrote
What are some that don't, and do they have any practical implications?
vickyswaggo t1_iww4a5e wrote
Calcium hydroxide (called slake lime and used in a lot of food chemistry)
[deleted] t1_iwyg1zd wrote
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Faelwolf t1_iwthn79 wrote
It would be close to the original saturation, if not the same, if the bottle remains sealed for at least 12 hours after thawing. The expandability of the container would be a determining factor, basically by determining the final ambient pressure for the duration. Boyle's + Henry's laws.
Ok_Construction5119 t1_iww47r2 wrote
This is not true. Solubility of solids decreases as temperature decreases, but solubility of gases increases as temperature decreases. See this image for reference:
https://chem.libretexts.org/@api/deki/files/125741/CNX_Chem_11_03_gasdissolv_2.jpg?revision=1
To answer OP's question, if, in an isolated system, you returned the system to its original state, the CO2 would redissolve into the solution.
Soda as you buy it is at equilibrium because of the pressure, around 2 psi. The CO2 spontaneously dissolves into the solution, and will again as long as you leave the receptacle unopened. For further information, you can read this:
[deleted] t1_iwtes1p wrote
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Still_Not-Sure t1_iwtnca8 wrote
I wonder if it were flash frozen… although flash freezing isn’t instantaneous…
perhaps in theory if you were to eject a strong enough container of soda into space….
Ok_Construction5119 t1_ix1i7gs wrote
The systems before the phase change from liquid to solid and after the phase change back from solid to liquid will be identical and so will their equilibrium states. It will just take time for the CO2 to dissolve back. It does not matter how quick or slow the phase change itself is.
urzu_seven t1_iwtrafq wrote
Soda freezes but bottle doesn't explode would be a rare scenario unless the bottle was previously opened and partly drained I'd bet.
[deleted] t1_iwu4yqo wrote
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Michkov t1_iwwzw9z wrote
Partially filled wouldn't work?
celo753 t1_iwxetoq wrote
Partially filled would already make your soda at least partially flat, since for your soda to be fizzy the liquid needs to be saturated with carbon dioxide, and having air in the container would make the liquid lose its carbon dioxide to that air.
You could have a high pressure carbon dioxide atmosphere inside your half-filled can, but then you come into a multitude of problems, like the fact that upon opening it would instantly explode like a shaken can of soda, and there would be very little liquid remaining for anyone to drink.
urzu_seven t1_iwy9bz6 wrote
Soda doesn’t go flat the second it’s opened. You can take some of it out and reclose the bottle. It will still have carbonation in it. But the point is freezing a full bottle of soda and unfreezing it is unlikely to work not because of carbonation change but because the bottle will burst due to expansion of the water.
urzu_seven t1_iwy9cd8 wrote
Why not?
Ok_Construction5119 t1_ix1dwgu wrote
This implies a rigid container that performs no pressure-volume work, but a bottle or can will change things!
[deleted] t1_ix2jkty wrote
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