Comments on: A question for everyone.

By: Chorius

Chorius — Tue, 08 Jan 2008 22:56:50 +0000

I have to agree with Drambuie, the main reason it didn’t freeze until after it was opened was the CO2, not the pressure. The pressure factors in by preventing the CO2 from coming out of solution, but the pressure alone could not change the freezing point. I got my degree in physics not chemistry, but yeah, the colligawhachamever properties… :)

So Coca Cola is correct, but for the wrong reason.

The soda was below freezing before the bottle was opened, then once the CO2 had a chance to escape the freezing point of the solution(coke) rose above it’s current temperature.

By: Susan

Susan — Sun, 06 Jan 2008 19:24:42 +0000

OK I don’t necessarily come here to laugh as you but I must admit the keys thing is rather funny. I say here chuckling to myself the whole time I read the “first time” story. Needless to say the better half looked at me rather strangely more than one. Oh well. Thanks for the laugh and as always a very entertaining read.
Here is just a hint on the locking your keys in the car thing. Use the key fob ONLY to lock the doors, never that oh so easy to hit button on the arm rest. Call it a lesson learned. :)

By: malficent

malficent — Sun, 06 Jan 2008 10:16:05 +0000

1. Shit happens

2. get over it

3. because they know that they are in good hand with TJ

4. Shit happens.

By: Drambuie

Drambuie — Sat, 05 Jan 2008 19:40:09 +0000

Kirk,
I know what the Coca Cola company says but looking at the phase diagram for water and the effect of pressure on the freezing point of water from the CRC Handbook (see my second post, it takes 4800 psi to drop the freezing point of water 2.5 C) and the fact that the bottles can withstand a maximum of 175 psi (according to the Coca Cola website) sort of negates the possibility that pressure in and of itself is the main contributor to the lowering of the freezing point. More likely it is the pressure which increases the solubility of the CO2 and therefore the total amount of solute in the soda which lowers the freezing point of the soda significantly (I think you can get about 0.5 moles of CO2 into a liter of water at 0C. Not sure since my chemistry book is at work and I had to use the constants in my head.)

By: Track

Track — Sat, 05 Jan 2008 16:35:08 +0000

1) I don’t know. Next question.
2) She needs to lay off gassy foods. Beans, beans, good for your heart… Beans, beans, GREAT for your heart!
3) I’m sorry, I was too busy eating gnomes and teabagging your dead dwarven allies to level an Alliance ‘lock to 70… though since they’re more EZ mode than Hunters, I’d think it’d take the same amount of time.
4) No, for one reason – It’d be like the blind leading the blind…through a minefield.

By: The Soldier

The Soldier — Sat, 05 Jan 2008 11:34:30 +0000

My science got pwned.

I phayle.

By: Euripedes

Euripedes — Sat, 05 Jan 2008 09:52:40 +0000

The idea of a man being insulted by farts and belchs puts me into hysterics.

By: Ratshag

Ratshag — Sat, 05 Jan 2008 03:50:59 +0000

1) Pressure and CO2 both is contributors, but since me specialty ain’t thermodynamics but rathers hitting things with me axe, I cannot say which is the greater factor.

2) Bugger should be glad she don’t eat my dragonbreath chili.

3) All the ‘locks on Team Ratshag is hordies, and is therefore subject to discrimination.

4) Sounds like a good job fer an underemplyed tank. Might need ta stack more avoidance first, though.

By: Kirk

Kirk — Fri, 04 Jan 2008 23:00:28 +0000

Drambuie,

According to Coca Cola company, the freezing point of Coca Cola, unpressurized, is 30 degrees F. Under pressure it’s lower yet, though the company does not tell the actual temperature.

So yes, CO is part of it but the main thing is the pressure.

By: Drambuie

Drambuie — Fri, 04 Jan 2008 19:41:05 +0000

@Kystofar
Absolutely, mmm coke slurpies! :) Coke is right that that pressure does lower the freezing point but I am pretty sure it is the colligative property of the dissolved CO2 in the liquid and not the actual pressure as it takes a tremendous amount to pressure to lower waters freezing point due to hydrogen bonding in liquid water. Theoretically you could figure it out by dissolving an equal amount (moles) of stuff (say sugar) in degassed and see if this depresses the freezing point more than the application of pressure to the degassed liquid (which should be incompressible). I have certainly been known to be wrong but either way it is a pretty cool phenomenon.