Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: neilep on 25/11/2008 11:57:00

Title: Why Does Sub Zero Beer Suddenly Freeze When Tapped ?
Post by: neilep on 25/11/2008 11:57:00

Dearest Peeps Of Inspirational Drink Imbibing Festive Joy,

Beer is my all time favourite alcoholic drink made from fermented cereals that I do not drink ! As a sheep I am of course tea total...it's true.

However, it did not stop me from sneaking into my neighbours lounge this morning and erecting this just for him

 [ Invalid Attachment ]

Considering the season I expect my neighbour ,who apparently is "on the wagon" (what ever that means !..and goes to some pace called AA every week)...anyway..he should be thrilled . especially as each bottle needs to be drunk.

 I saw a neat thing on Market Kitchen the other day. This klevur bloke cooled a bottle of beer to below zero and it was still liquid...as clear as day it was and no mistake ! .....but...when he tapped the bottle...the beer started to crystallize and freeze before your very eyes....It was well kewl !


Why did that happen ?...why did the beer remain liquid at sub zero temperature until a klever bloke tapped the bottle  ?

Oh, I think my neighboour has discovered his Chrimbo Alcy Gift...I can hear him shouting 'Noooooooo'....awwwwwww....... he is clearly humbled by my going to so much trouble.....awwwwww...that's so sweet......as a new years gift I am sure he will enjoy my rendition of the Great Wall of China made from packs of cigarettes....I know he's trying to quit and I'm sure this will help him in  a metaphorical obstacley kind of way !


Hugs & Shmishes


mwah mwah mwah mwah



Neil
Gottle Of Geer

xxxxxxxxxxxxxxxxxxxxxxxxxxx

Title: Why Does Sub Zero Beer Suddenly Freeze When Tapped ?
Post by: dentstudent on 25/11/2008 12:09:58

This used to happen to me in the Black Forest winters - beer cooling nicely outside (much cheaper than a fridge) but too cold in some cases. It was often between -10°C and -20°C, and when I opened the bottles that were clear, they would instantly become crystalised and undrinkable. It's all about our old friend, nucleation sites. The action of opening the bottle, or in your case, tapping them, brings a bubble out of solution, against which other crystals/bubbles can form. The beer was able to be below freezing due to 1) the alcohol content (antifreeze) and 2) the pressurised container. 

Title: Why Does Sub Zero Beer Suddenly Freeze When Tapped ?
Post by: neilep on 25/11/2008 12:24:22

Quote from: dentstudent on 25/11/2008 12:09:58

This used to happen to me in the Black Forest winters - beer cooling nicely outside (much cheaper than a fridge) but too cold in some cases. It was often between -10°C and -20°C, and when I opened the bottles that were clear, they would instantly become crystalised and undrinkable. It's all about our old friend, nucleation sites. The action of opening the bottle, or in your case, tapping them, brings a bubble out of solution, against which other crystals/bubbles can form. The beer was able to be below freezing due to 1) the alcohol content (antifreeze) and 2) the pressurised container. 

Coooooool !! THANK EWE DENSTUDENT

Nice gateaux ! (actually..it's a little sickly for me...it is dark choccy and cherry isn't it ? )

Nucleation eh ...erhmmm....what's that ?  Sounds like a term used to designate a country that gets all it's power from a Nuclear station !  [;)]

Title: Why Does Sub Zero Beer Suddenly Freeze When Tapped ?
Post by: dentstudent on 25/11/2008 12:47:25

Here's an interesting nucleation fact from Wiki:

"Pure water freezes at −42° C rather than at its freezing temperature of 0° C if no crystal nuclei, such as dust particles, are present to form an ice nucleus." (http://en.wikipedia.org/wiki/Nucleation)

Seems very low! But without particles within the liquid, then others cannot form, and so the liquid is super-cooled but not ice.