Magic

[Lindsey 0]

It's evil....just like Stinky Gringo Margaritas. Someone smarter than me explain it to me. Say ya' have a little 200 mL Stinky Gringo margarita in the little plastic bottle it comes in. The Stinky Gringo is 36 proof. Ya' keep 'em in the freezer. Comes time to enjoy one, ya pull it from the fridge in its seemingly original liquid phase. But when ya' shake it a little, small clumps of an apparently icy substance precipitates out. Then very quickly, the whole thing....the whole Stinky Gringo turns into a slushy icy drink. Why does that happen???? Why does it turn icy when you take it OUT of the freezer? I need answers.

--
A conservative is just a liberal who's been mugged. A liberal is just a conservative who's been to jail

[kschilk 0]

That isn't slush....when ya' shook it, ya' made it cum!

"T'was ever thus."

[Lindsey 0]

Quote

That isn't slush....when ya' shook it, ya' made it cum!

Okie dokie then....ummm....next person smarter than me? Have any good scientific explanations...lol.

--
A conservative is just a liberal who's been mugged. A liberal is just a conservative who's been to jail

[kallend 1,635]

Quote

It's evil....just like Stinky Gringo Margaritas. Someone smarter than me explain it to me. Say ya' have a little 200 mL Stinky Gringo margarita in the little plastic bottle it comes in. The Stinky Gringo is 36 proof. Ya' keep 'em in the freezer. Comes time to enjoy one, ya pull it from the fridge in its seemingly original liquid phase. But when ya' shake it a little, small clumps of an apparently icy substance precipitates out. Then very quickly, the whole thing....the whole Stinky Gringo turns into a slushy icy drink. Why does that happen???? Why does it turn icy when you take it OUT of the freezer? I need answers.

It's a nucleation problem. Google "heterogeneous nucleation" and "homogeneous nucleation".

In a nutshell, formation of an ice crystal requires a nucleus, and that nucleus is very hard to form all by itself (homogeneous) so a solution may become supercooled. Shaking it introduces nucleation sites (heterogeneous nucleation) so that the ice crystals now have something to grow on.

Same reason that an unshaken can of soda doesn't fizz much when opened, but a shaken can fizzes violently.

...

The only sure way to survive a canopy collision is not to have one.

[n23x 0]

Does this go the other way, such as heating deionized water and then throwing something in it to cause it to boil?

(I didn't want to google it).

.jim

"Don't touch my fucking Easter eggs, I'll be back monday." ~JTFC

[Lindsey 0]

Thanks Professor. That's my favorite thing I've learned so far today. :)

This day is starting off pretty good. Besides learning this little tid-bit, a patient just prayed for my intimacy in the ER. HA! Hope it helps.

Peace~
linz

--
A conservative is just a liberal who's been mugged. A liberal is just a conservative who's been to jail

[kallend 1,635]

Quote

Does this go the other way, such as heating deionized water and then throwing something in it to cause it to boil?

(I didn't want to google it).

.jim

Yes.

...

The only sure way to survive a canopy collision is not to have one.

[SpeedRacer 1]

It's all Bill Clinton's fault.

Or global warming.

one or the other.

Speed Racer
--------------------------------------------------

[kallend 1,635]

Quote

Thanks Professor. That's my favorite thing I've learned so far today. :)

This day is starting off pretty good. Besides learning this little tid-bit, a patient just prayed for my intimacy in the ER. HA! Hope it helps.

Peace~
linz

Just amplifying a bit on my soda can comment:

A lot of people think that shaking a can or bottle of soda increases the pressure. It doesn't (unless the can was only recently sealed). When the can is opened any CO2 bubble nucleus that forms and is smaller than about 1 micrometer across will actually shrink due to its surface tension. So to get much CO2 evloution you need bubbles bigger than this, which will grow. The way you get them is by shaking.

When you pour the soda slowly into a glass you will notice very few bubbles forming randomly in the liquid. You generally see streams of bubbles coming from spots on the bottom and sides of the glass. These sites are either specks of dirt acting as nuclei (eeeuwww) or microscopic cracks in the glass surface which also act as nuclei for bubble formation.

Bottled Guinness contains a bubble nucleating device to ensure that the famous "head" forms properly.

...

The only sure way to survive a canopy collision is not to have one.

[1969912 0]

Quote

Bottled Guinness contains a bubble nucleating device to ensure that the famous "head" forms properly.

Thanks.

I had always thought (incorrectly) that the "Guinness Widget" simply emitted gas through a tiny orifice(s) after opening the bottle, and that those bubbles were what formed the head. After seeing your post, I looked more closely, and yes, it's a nucleating device, not just a "bubbler".

The widget contains carbonated stout with a compressed gas headspace. The compressed gas pushes the stout through the orifice, and shearing of the liquid at the orifice forces dissolved gas out of solution. So what you get is a high speed stream of tiny bubbles/liquid squirting around inside the bottle, and each bubble is a potential nucleation site for dissolved gas contained in the rest of the stout.


Here's the US patent (USPTO no. 4,832,968) for the Widget. A detailed description of its operation is given.

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=AND&d=PTXT&s1=4,832,968.PN.&OS=PN/4,832,968&RS=PN/4,832,968


Pretty clever invention.

"Once we got to the point where twenty/something's needed a place on the corner that changed the oil in their cars we were doomed . . ."
-NickDG