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Author Topic: Why should shaking a jug of hot water make it expand?  (Read 1270 times)

Offline thedoc

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Jodie Rio  asked the Naked Scientists:
   
I noticed something strange today while cleaning out milk jugs that I hope you can help with. I partly filled them with hot water, screwed on the lid, shook them and they expanded like an inflating balloon.

At first I thought it was just the steam making them expand, but when I didn't shake them they didn't expand, even though the water temp in both was the same. Do you know why the shakened jugs have this reaction?

From Jodie Rio

What do you think?
« Last Edit: 05/08/2013 05:30:02 by _system »


 

Online syhprum

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Re: Why should shaking a jug of hot water make it expand?
« Reply #1 on: 05/08/2013 19:33:42 »
I think it is because the shaking releases the dissolved gases in the water.
 

Offline Bored chemist

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Re: Why should shaking a jug of hot water make it expand?
« Reply #2 on: 05/08/2013 19:41:02 »
It's likely that shaking them meant that the water heated up the air which expanded.
If they are not shaken then the poor conductivity of air means that only the bit near the water surface gets heated.
 

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Re: Why should shaking a jug of hot water make it expand?
« Reply #2 on: 05/08/2013 19:41:02 »

 

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