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Author Topic: Why do teabags inflate when you pour on hot water?  (Read 3316 times)

paul.fr

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When you pour hot water over a teabag, it inflates. Why?
« Last Edit: 04/03/2008 23:32:12 by chris »


 

Offline DoctorBeaver

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Re: Why do teabags inflate when you pour on hot water?
« Reply #1 on: 25/02/2008 07:54:08 »
They inflate? I wouldn't know about that. I use Twining's specialist infusions and they come as loose leaf.
 

lyner

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Re: Why do teabags inflate when you pour on hot water?
« Reply #2 on: 25/02/2008 09:10:13 »
I think this is along the lines of the fizzy coke question. The hot water, once it gets inside the teabag, becomes full of tiny 'nuclei' for air bubbles to form around and the air in these bubbles is trapped inside the bag.
A good experiment would be to compare the inflation of a bag with boiled fresh water and one with over - boiled water, in which you'd expect less dissolved air.
Go on, you young experimenters.

A similar thing can happen if you put instant coffee into water which has been heated in a microwave oven; the erruption is quite a hazard, in fact. In this case it may be also because the water becomes super-heated and emerges from the oven at above 100C; same basic Physics at work though.
« Last Edit: 25/02/2008 09:12:29 by sophiecentaur »
 

The Naked Scientists Forum

Re: Why do teabags inflate when you pour on hot water?
« Reply #2 on: 25/02/2008 09:10:13 »

 

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