Author Topic: Temperature Dependency for Time to Reach Solubility Equilibrium  (Read 1139 times)

Offline abraxas

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Temperature Dependency for Time to Reach Solubility Equilibrium
« on: January 11, 2011, 09:14:05 AM »
Liquid will absorb more CO2 at a lower temperature at a given pressure, this is simple.  But for two different temperatures and pressures corresponding to a similar solubility equilibrium won't the higher temperature reach equilibrium much quicker?  Intuitively it seems like this would follow a 10C = 2x the speed rule of thumb from chemistry, unless I am missing something.

So if I were to force carb at 65F (26psi) outside of my kegerator instead of 45F (15psi), I would think that I could expect to do it in 4-5 days instead of the 8-10 I typically experience in my kegerator?  

This is relevant because I have 4-5 beers I would to carb up and enter into a competition in a month or so.  After nice long lagering/conditioning I hate to go with a shake method to achieve carbonation as I just don't know how long it would take to resettle everything back out.  I will go with a burst technique but I am thinking I should bring them out of the 32F lagering stage to a 50F room just for the carbonation period.

Offline morticaixavier

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Re: Temperature Dependency for Time to Reach Solubility Equilibrium
« Reply #1 on: January 11, 2011, 09:22:14 AM »
I know nothing about this level of stuff but... Wouldn't it depend on the temp you intend to serve it at? if yo carb to your desired level at 50 but serve at 45 wouldn't it be undercarbed still?
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Offline abraxas

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Re: Temperature Dependency for Time to Reach Solubility Equilibrium
« Reply #2 on: January 11, 2011, 09:25:59 AM »
I know nothing about this level of stuff but... Wouldn't it depend on the temp you intend to serve it at? if yo carb to your desired level at 50 but serve at 45 wouldn't it be undercarbed still?

No...You'd carb it to a standard volumes CO2 per volumes beer (0 C.–760mm.) which is what the charts are based on.  Once it was there it'd stay there regardless of the temperature.
« Last Edit: January 11, 2011, 09:28:03 AM by abraxas »

Offline tschmidlin

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Re: Temperature Dependency for Time to Reach Solubility Equilibrium
« Reply #3 on: January 11, 2011, 10:23:38 AM »
That's an interesting idea.  I can see what you're saying, but for some reason I don't think it works that way.  You should certainly test it though, I could easily be wrong.
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Offline a10t2

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Re: Temperature Dependency for Time to Reach Solubility Equilibrium
« Reply #4 on: January 11, 2011, 04:48:59 PM »
But for two different temperatures and pressures corresponding to a similar solubility equilibrium won't the higher temperature reach equilibrium much quicker?  Intuitively it seems like this would follow a 10C = 2x the speed rule of thumb from chemistry, unless I am missing something.

Unfortunately, this isn't a chemical reaction. Dissolving a given amount of CO2 will take roughly the same amount of time no matter what the temperature - actually, it would probably be slightly faster at lower temperatures.
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Offline abraxas

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Re: Temperature Dependency for Time to Reach Solubility Equilibrium
« Reply #5 on: January 11, 2011, 05:23:17 PM »
Unfortunately, this isn't a chemical reaction. Dissolving a given amount of CO2 will take roughly the same amount of time no matter what the temperature - actually, it would probably be slightly faster at lower temperatures.

I'm no chemist but I really struggle with this, it's just so counter-intuitive for me.  I mean at a higher temperature the CO2 is going to be moving more quickly which to me, by collision theory given a set surface area is going to result in a quicker equilibrium.

Offline tschmidlin

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Re: Temperature Dependency for Time to Reach Solubility Equilibrium
« Reply #6 on: January 11, 2011, 11:12:20 PM »
Unfortunately, this isn't a chemical reaction. Dissolving a given amount of CO2 will take roughly the same amount of time no matter what the temperature - actually, it would probably be slightly faster at lower temperatures.

I'm no chemist but I really struggle with this, it's just so counter-intuitive for me.  I mean at a higher temperature the CO2 is going to be moving more quickly which to me, by collision theory given a set surface area is going to result in a quicker equilibrium.
It's not chemistry, it's physics.   Unfortunately, I'm not a physicist. ;D But remember, at a warmer temperature it will also leave the beer faster so that may balance it out.
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Offline MDixon

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Re: Temperature Dependency for Time to Reach Solubility Equilibrium
« Reply #7 on: January 12, 2011, 03:11:18 PM »
I don't actually know, but if the Volumes of CO2 were equal I would think they would carbonate in the same time OR the cold would carbonate quicker due to the higher solubility at cold temps.
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Offline a10t2

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Re: Temperature Dependency for Time to Reach Solubility Equilibrium
« Reply #8 on: January 12, 2011, 04:07:43 PM »
Chemistry is just applied physics. ;D
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Offline tschmidlin

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Re: Temperature Dependency for Time to Reach Solubility Equilibrium
« Reply #9 on: January 12, 2011, 04:25:22 PM »
Chemistry is just applied physics. ;D
Isn't physics just applied math? ;D
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Re: Temperature Dependency for Time to Reach Solubility Equilibrium
« Reply #10 on: January 12, 2011, 05:14:57 PM »
Physics:Math::Sex:Masturbation ;)

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