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Author Topic: Dry Ice  (Read 17010 times)

Offline rosy

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Re: Dry Ice
« Reply #25 on: 06/09/2005 22:42:38 »
Liquid nitrogen boils at about 80K (-190C ish). Dry ice, solid CO2, sublimes direct to the gas at about -77C (195K ish). So yeah, you're right, liquid N2 is colder than solid CO2.


Offline anthony

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Re: Dry Ice
« Reply #26 on: 07/09/2005 12:01:45 »
The answer you're looking for is crazing. Your cup was probably high density polystyrene, though it doesn't need to be for the effect. The acetone creates areas of low density (crazes) within the plastic, these have a lower refractive index than the surrounding plastic and so scatter light. And why is the sky blue? Small particles scatter light selectively, blue in preference. This effect of the cold is curious, these areas in the plastic must be amorphous, and so expand in the cold, plastics do this. The chances of you achieving this effect if you wanted to are slim, so well done!

Offline Equalizzer

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Re: Dry Ice
« Reply #27 on: 13/11/2005 19:42:13 »
where could i get hold of dry ice

I Know A Good Experiment:
mix, H2O and H2O and you get, well, just H2O. =p

Offline Ylide

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Re: Dry Ice
« Reply #28 on: 14/11/2005 20:52:07 »
It's sold in the supermarket here, not sure about across the pond.  

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Re: Dry Ice
« Reply #28 on: 14/11/2005 20:52:07 »


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