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Author Topic: How do bubbles (and crystals) form?  (Read 4256 times)

Offline JimBob

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How do bubbles (and crystals) form?
« on: 15/03/2009 23:12:46 »
I just boiled some water for cooking noodles. As the water came to a boil bubbles started to form. Where and how do they form?

I believe that I have read the form on "nucleation locations" where the phase change occurs but how and why?

I also know that crystals - the liquid to solid phase change - also take place at nucleation locations. Again, how and why? It is probably very closely related.
« Last Edit: 15/03/2009 23:15:07 by JimBob »


 

Ethos

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How do the bubbles form?
« Reply #1 on: 15/03/2009 23:15:28 »
I just boiled some water for cooking noodles. As the water came to a boil bubbles started to form. Where and how do they form?





Look up surface tension in Wikipedia.
 

paul.fr

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How do bubbles (and crystals) form?
« Reply #2 on: 15/03/2009 23:50:45 »
Isn't the liquid water turning gasseus due to superheating around the element? Sure that 'Sophie' will have a better the correct answer.
 

Offline JimBob

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How do bubbles (and crystals) form?
« Reply #3 on: 16/03/2009 02:46:12 »
I just boiled some water for cooking noodles. As the water came to a boil bubbles started to form. Where and how do they form?






Look up surface tension in Wikipedia.


Please note that I included another phase change (crystal formation) in the question. Also, it does not explain why the bubbles formed at the same place over and over again.
 
 

Offline Chemistry4me

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How do bubbles (and crystals) form?
« Reply #4 on: 16/03/2009 04:23:41 »
Air becomes less soluble in water as the temperature goes up.
 

Offline LeeE

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How do bubbles (and crystals) form?
« Reply #5 on: 16/03/2009 14:10:49 »
I believe that I have read the form on "nucleation locations" where the phase change occurs but how and why?

I think this is because the two different states have overlapping ranges.  Without a trigger, there is no reason for the state to change if it moves from a region where there is no overlap to the overlapping region, but if there is a trigger it may cause the state to flip as either state is valid at that point.
 

Offline neilep

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How do bubbles (and crystals) form?
« Reply #6 on: 16/03/2009 17:27:28 »
I'm the only one allowed to ask about bubbles !!..and then I must repeatedly ask the same question about bubbles every 13 months !!.......oh...and then delete the thread and look embarrassed !!  [:-[] [:-[]
 

blakestyger

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How do bubbles (and crystals) form?
« Reply #7 on: 16/03/2009 18:15:27 »
Bubbles form when the vapour pressure within the liqiud starts to exceed that above it.
 

Offline Bored chemist

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How do bubbles (and crystals) form?
« Reply #8 on: 16/03/2009 20:42:30 »
Bubbles form when the vapour pressure within the liqiud starts to exceed that above it.
Not reliably they don't. Sometimes they superheat then "bump" violently.
 

Offline yor_on

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How do bubbles (and crystals) form?
« Reply #9 on: 16/03/2009 22:32:01 »
It's a gas reading you all :)
 

Offline LeeE

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How do bubbles (and crystals) form?
« Reply #10 on: 18/03/2009 06:47:34 »
You're just fuming because you didn't get your answer in first.
 

Offline Chemistry4me

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How do bubbles (and crystals) form?
« Reply #11 on: 18/03/2009 06:53:00 »
Whoa, that comment had some heat on it.
 

Offline Madidus_Scientia

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How do bubbles (and crystals) form?
« Reply #12 on: 18/03/2009 19:37:36 »
Yeah, don't fire up
 

Offline dlorde

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How do bubbles (and crystals) form?
« Reply #13 on: 18/03/2009 20:58:55 »
Not reliably they don't. Sometimes they superheat then "bump" violently.
Indeed, and if you put a clean cup of tea into a microwave and heat it for longer than you should, then make the mistake of dropping sugar (or sometimes even just a spoon) into it, it can bump explosively, showering you with superheated tea. Many people have been badly scalded as a result of such 'accidents'.

p.s. DON'T TRY THIS AT HOME!
 

The Naked Scientists Forum

How do bubbles (and crystals) form?
« Reply #13 on: 18/03/2009 20:58:55 »

 

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