Viewing a single comment thread. View all comments

InTheEndEntropyWins t1_j2dms4b wrote

I'm pretty sure that it would prevent the drink from going flat, based on my knowledge of chemistry.

Please can you explain why you don't think it would help.

1

dantodd OP t1_j2e5rpg wrote

Of course. Soda is carbonated by dissolving carbon dioxide gas into the base drink. You can dissolve other gases into liquid too. For example nitrogen dissolved into a liquid is pretty common and they call it "nitro" which is where a nitro stout beer and nitro coffee get their names from. In fact, I just saw nitro Pepsi on the shelf the other day for the first time.

So, now we have a gas dissolved into our liquid. As the gas escapes the solution it comes out in the form of bubbles. And what we are trying to prevent is all the bubbles escaping from the soda left over in the bottle..

In order to prevent the gas escaping you want to apply pressure to the liquid. You can imagine it like the high pressure prevents the bubbles from growing larger and coming out of the solution.

You can see this every day in a plastic soda bottle. When all the CO2 is in solution the bottle is very hard. If you open a bottle and then pour out half the bottle and put it in a large cup in the counter and then tightly reseal the bottle. After a few hours the bottle will be very hard and the suits inside will still be carbonated but the soda you poured out will be flat, the gas will have mostly escaped. The same volume but one under pressure container in the bottle but the other open to just atmospheric pressure.

This is because the CO2 in the bottle begins to come out of solution just like the open cup but the bottle holds in the gas that does escape so high pressure builds again and prevents the rest of the by gas from coming out of solution which means your soda is still carbonated though at a slightly lower level than a new bottle.

(In brewing beer is often carbonated simply by pressurizing containers of flat beer with CO2 and the high pressure will force CO2 into solution thus carbonating the beer. )

If you squeeze all the air out of the 2 litter bottle all you are doing is removing air from the bottle. The gas still inside the soda is going to continue coming out of solution until it reaches equilibrium with the pressure in the bottle but a lot more gas will have to come out before that happens because there is less air inside the bottle to begin with.

0

InTheEndEntropyWins t1_j2e82hx wrote

I think I agree with pretty much everything you said, but it seems like that supports the idea of removing any air or space for the CO2 to escape to.

By squeezing out the air you are effectively removing the volume of 1 atmosphere pressure for the CO2 to escape to. With the extreme case you are effectively increasing the atmospheric pressure to many magnitudes/infinite.

>The gas still inside the soda is going to continue coming out of solution until it reaches equilibrium with the pressure in the bottle but a lot more gas will have to come out before that happens because there is less air inside the bottle to begin with.

Go out to where? It's gong to have to overcome the pressure of the physical bottle, which is going to be way over 1.

Let's use the example of a metal bottle, how does a drink go flat in a metal bottle without any air in it? You don't even need a metal bottle, just use a normal unopened bottle, how does a normal bottle of coke go flat? It doesn't since there is only a tiny amount of air for the CO2 to go into.

What's your explanation for how an unopened bottle of coke doesn't go flat?

1

dantodd OP t1_j2ebuif wrote

>Go out to where? It's gong to have to overcome the pressure of the physical bottle, which is going to be way over 1. The gas will go into the bottle. The squeezed bottle will just be filled with CO2 to the point of deforming until it either reaches the equilibrium pressure. Of course if you remove almost all the air the CO2 will escape the soda but the pressure in the bottle will not go over one atmosphere so you have perfectly flat soda.

>Let's use the example of a metal bottle, how does a drink go flat in a metal bottle without any air in it? You don't even need a metal bottle, just use a normal unopened bottle, how does a normal bottle of coke go flat? It doesn't since there is only a tiny amount of air for the CO2 to go into.

The CO2 doesn't go "into the air" it goes "out of the soda" which may seem a small difference but it is the gas pressure in the bottle that keeps the CO2 dissolved and this the soda carbonated. If you placed that in an open vacuum with no air at all it would go flat even faster because of the pressure differentiall. (There is less pressure holding the gas in solution) the CO2 will continue to leave the soda until the gas itself builds up enough pressure to hold what's left in solution. If there is a lot of air in the bottle it will take less CO2 to build up that pressure. If you remove the air it will take more CO2 to build up that pressure. Squeezing a bottle didn't reduce its volume, only the volume of air inside that must be filled by CO2 if it is ever going to reach equilibrium pressure. If you squeeze a bottle from the store before opening it you will know how much pressure it takes to keep CO2 in solution for "full carbonation" there is no way for a bottle with the air evacuated will resist anything close to that much pressure so as the CO2 is released the bottle will start expanding to accept the CO2 but there is not enough CO2 to replace all the air quizzes out do the dogs hours flat long before at reaches equilibrium pressure.

0

InTheEndEntropyWins t1_j2ed1f5 wrote

>The CO2 doesn't go "into the air" it goes "out of the soda"

If there is no where for it to go to, then it can't go "out of the soda". Are you suggesting it goes into the plastic bottle? But then how do unopened bottle of soda stay fizzy?

>If you placed that in an open vacuum with no air at all it would go flat even faster because of the pressure differentiall.

How the hell is there an open vacuum if they have squeezed out the air?

>Squeezing a bottle didn't reduce its volume

Maybe I'm misunderstanding what you mean but squeezing a bottle reduces the volume. Just try squeezing a bottle to remove the air and tell me how the volume hasn't reduced.

Just post a picture of a bottle you have squeezed, removing the air that has the same volume.

1

dantodd OP t1_j2eef6r wrote

I'm afraid I'll have to leave it to you too perform your own experiences or Google searches for some explanation that makes more sense to you.

0

InTheEndEntropyWins t1_j2egw2a wrote

I mean by definition, or experiment if you squeeze the air out of a plastic bottle the volume would reduce. I would post a picture, but seriously pretty much every person who has every interacted with a plastic bottle would know that squeezing it would reduce the volume.

Are you a real person or are you some kind Chat GPT AI that has never actually touched a plastic bottle?

Edit: I'm tempted to post a LPT about how you shouldn't bother engaging with people who don't think the volume in a plastic bottle reduces if you squeeze the air out of it.

Edit 2: Just do the experiment, empty two bottle half way, squeeze the air out of one so there is pretty much no air/space left. Leave for a few days then see if there is any difference in fizziness.

Edit 3: Evidence the the volume reduces when you squeeze the air out https://qph.cf2.quoracdn.net/main-qimg-3d07ddd8eb1f5d84fb83848a9bdc144f.webp

1