Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Marco on 24/01/2009 23:20:52
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Marco asked the Naked Scientists:
Dear NS crew,
Listening in on podcast from the Canada/US. LTS!
I very much enjoy your science news blitz and fast-paced format.
Can you answer a question for me about frozen water?
My mom and I have found that the water we had in a large plastic pail had frozen and when I had chipped it out with an ice pick the ice was clear everywhere but a small area in the lower-middle where the ice was discoloured and seemed to have contained in it all the impurities and dust particulates in the water.
When I freeze water for ice cubes I notice the same thing happening, but
it was much more visible with the larger volume of water in the pail.
My mom was wondering if this is a way to purify water? Would chemicals
also be forced out of the frozen water is the way salt is removed in the Arctic when icebergs form?
What is happening here?
Thanks!
Marco3
What do you think?
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I think maybe some of the impurities will be removed, but I wouldn't bet on it, as in producing drinking water from a pond.
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when you freeze water, the freezing process is a distillation or purification process. When the ice forms, impurities that exist in the water are ejected from the ice while it freezes, so the ice is always purer than the water from which it formed
http://www.arcticclimatemodeling.org/faq_snow_ice.html
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So when in the desert?
SAS someone?
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I read about using a plastic rifled sheet to get water?
Not that I'm planning to try but?
Would it work.
I've seen figures stating that you would need something amounting to five liters a day?
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Yes, it's most definitely a wrong question, considering the tread.
What can I say?
Low attendance threshold?
Never mind no matter:)
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I read about using a plastic rifled sheet to get water?
What is it? [???][???][???]
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Well, you are expected to use it at mornings when condensation will, 'lead' by the rifles, place water at your cans disposal.
Could be a 'urban myth' though :)
But I've always had a weakness (?) for them:)
Ah, urban legends that is.
But yes, I have to admit to consider the SAS as the elite of the elite.
When it comes to endurance and 'free thinking'.
That doesn't mean that other won't do some things better.
Samoa seems to have a very 'educated' 'special force' if I remember right?
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I knew that i remembered wrong here:(
What I tried to remember there was not Samoa, although Samoans are well known to be extremly fierce warriors.
It was the Republic of Fiji Military Forces Commandos who for the last fifteen (?) years been the winners of the Forces Spéciales Competion D'Élite Internationale in Albertsville.
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But SAS do have my heart:)
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maybe I should I call it 'stripes' instead of 'rifles', or 'lines'?
awh, English :)
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Btw: condensation will also be purifying.
So?
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Samoa seems to have a very 'educated' 'special force' if I remember right?
I doubt it! [:D][:D]
What is the motto for the SAS? It has suddenly disappeared from my head [???][???][???]
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Should I call it 'stripes' instead of 'rifles', or 'lines'?
So?
Oh! Now I know what you mean! Call it strips [:)][:)]
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I would say it's hearts and minds.
Depending:)
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Who Dares Wins, aha! That's the one! Funny motto, don't you think?
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Really?
:)
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Yes! Of course!
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So do you know?
Would it work?
I've seen some other tricks where you dig a hole in the sand.
But i kind of liked the idea of a plastic sheet?
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Try to goggle on SAS hearts and minds.
And no, I didn't.
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Maybe we should move this conversation to the "Do you have STB syndrome" thread!
I've put my next post there [:)]
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maybe?
Anyway, 'hearts and minds' is what makes SAS into a elite force to my eyes:)
It's a very good idea, and it will work, if 'allowed' and supported.
So much better that cowardly rocket attacks on unsuspecting 'targets'.
That as it do has a 'moral' quality to it, don't you think?
That and sheer 'guts'.
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Post your next one here (http://www.thenakedscientists.com/forum/index.php?topic=19703.msg220836#new)
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Awh, now I'm having 'two' conversations with you:)
Does that make me a 'schizo'
Or do I just need to get my eyes checked?
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Or do I just need to get my eyes checked?
No, you don't. But I do.
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I think we both do :)
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Btw: thanks for 'strips' Chem.
I'm not joking when stating that English words can be difficult to 'pinpoint'.
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(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fbestsmileys.com%2Flol%2F4.gif&hash=dc0017defb1737ae43c0ff6efcb35b2a), you're a funny man Mr. yor_on!(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fbestsmileys.com%2Flol%2F4.gif&hash=dc0017defb1737ae43c0ff6efcb35b2a),
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Chem, it was you who asked.
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And the real 'motto' is different from 'unit' to unit'.
As I understand it soldiers use it to espy the sheep's from the wolfs:)
Well, sort off.
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Well there was also: Train hard, fight easy (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fbestsmileys.com%2Fsuperhero%2F1.gif&hash=dc0d80a8c82070f1b8035abef4468c84). Train easy, fight hard - and die...(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fbestsmileys.com%2Fviolent%2F10.gif&hash=35929479ff319d2333d0f8aac1e835df) (without the smiley(man)/deadeys)
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Chem, it's cool:)
http://www.strategypage.com/militaryforums/516-199.aspx
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Going back to the original post for a mo.
As water begins to freeze, it crystalises, becomes lighter than the rest of the water so rises toward the surface. Impurities heavier than the ice will tend to stay in the unfrozen water. This would continue to happen until many of the impurities are left below the ice, at the bottom of your bucket.