Question about the structure of ice

Originally posted by wolfgang59
How can you distil the H+ (shouldnt that be H3O+ ??) and OH- out of water? Isnt that a natural phenomenon?

It's not a distillation. It's deionization. The water is run through an electric current I believe which attracts anything with a charge.

The H30+ and OH- will regenerate themselves however.

Originally posted by sonhouse
I booked that site. The first image there shows 12 molecules. Isn't that the minimum? How can it have the hex pattern with less than 12?

You only need 6 to make the hex pattern, though it might not be stable.

Originally posted by AThousandYoung
You only need 6 to make the hex pattern, though it might not be stable.

I think the stable part of your statement is true, the 12 molecules represent two hexes linked together vertically, which sounds to me like it would have to be more stable than a single hex structure hanging out by itself. Maybe it would take 18 molecules to be stable, like one center hex and one above and one below. Sounds sort of reasonable to me. Then of course the more the merrier, stability wise, as it approaches a bulk material.

Originally posted by AThousandYoung
It's not a distillation. It's deionization. The water is run through an electric current I believe which attracts anything with a charge.

The H30+ and OH- will regenerate themselves however.

isnt de-ionised water just pure water? (ie with all the salt ions removed) I dont think it refers to H3O+, OH- ions.

De-ionised water is the stuff you used to have to use for your steam iron.

Originally posted by wolfgang59
isnt de-ionised water just pure water? (ie with all the salt ions removed) I dont think it refers to H3O+, OH- ions.

De-ionised water is the stuff you used to have to use for your steam iron.

De-ionized water can still have neutral particles in it I would imagine, so it's not necessarily pure. And no, the hydronium and hydroxide ions aren't what's being targetted, but they would be removed during the process I would think.

Filtration or a centrifuge would remove insoluble material I guess.

I think de-ionisation is just to remove soluble bits and bobs (eg limescale). Living in a hard water area I know just how annoying (and what damage) those soluble bits n bobs do!

Originally posted by wolfgang59
isnt de-ionised water just pure water? (ie with all the salt ions removed) I dont think it refers to H3O+, OH- ions.

De-ionised water is the stuff you used to have to use for your steam iron.

What you have in a common household iron is distilled water, not de-ionized. Distilled water usually comes from steam which they cool and collect. Most of the contaminants like salt are removed but distilling can't remove everything. You can tell the level of de-ionization by the conductivity. Fully de-ionized water has an electrical resistance of about 18 megohms per square cm, the standard for DI water. Distilled water would measure a few hundred thousand ohms on the same scale. The difference is DI water can be used to cool equipment that has to be at a high voltage. I worked for decades on a device called an Ion Implanter, google it for details, but there is section that develops as much as a half million volts for ion acceleration. But that section generates heat that must be gotten rid of, so the problem becomes how do you get rid of excess heat across a voltage barrier of hundreds of thousands of volts?
The old way was to use liquid freon which is an extremely good insulator but liquid and holds quite a bit of heat, the specific heat index is not quite as high as water but it can carry off enough to work so they circulate this freon around up polyflow tubing across the voltage barrier and into the machine where heat is extracted then the freon is off to a heat exchanger at ground voltage level and off again goes that freon back to the machine, etc. That was the way it was done for decades but then they found out the downside of freon, killing the ozone layer and it was made illegal to use like that. So in comes DI water, also an extremely good insulator and has even higher specific heat than freon so it is a win-win situation. It crosses the high voltage barrier, can be used in exactly the same way, carries of excess heat. The only problem is, DI water has an affinity to metals, the polar nature of the molecule in the pure state that is DI water will tear off microscopic bits of metal used as say, fitting, in the plumbing of the heat removal circuit. So it called for a redesign of system components that now use some kind of teflon or kevlar or similar plastic in the fittings required for the heat control system. Plastic is not for some reason which I don't know why, is not attacked by the DI water, I guess it has to due with the kind of chemical bonds inherent to metals but the net result is the DI water maintains its purity pretty much forever in the face of exposure to plastic like teflon whereas with metal fittings, they get eaten away, which has two effects: The first is the fitting eventually starts to leak and there goes your DI water and the second is now the DI water is no longer DI but closer to just distilled water and as such, exhibits a much lower resistance and so will arc through the water path which defeats the purpose for the DI water in the first place, so the gist of that is, if you have a circulating DI water system, you better not have ANY metal in contact with it because it tears apart metals on a molecular level. It is pretty much only water molecules and nothing but, maybe with some neutrals but no other substance like minerals or metals.

Originally posted by sonhouse
What you have in a common household iron is distilled water, not de-ionized. Distilled water usually comes from steam which they cool and collect. Most of the contaminants like salt are removed but distilling can't remove everything. You can tell the level of de-ionization by the conductivity. Fully de-ionized water has an electrical resistance of about 18 ...[text shortened]... ules and nothing but, maybe with some neutrals but no other substance like minerals or metals.

Plastic is not for some reason which I don't know why, is not attacked by the DI water, I guess it has to due with the kind of chemical bonds inherent to metals

Possibly it's because plastic molecules are covelantly linked to one another and are nonpolar and nonpolarizable (I think), whereas the metals are easily polarizable and the atoms are not covalently bonded to one another.

Originally posted by AThousandYoung
[b]Plastic is not for some reason which I don't know why, is not attacked by the DI water, I guess it has to due with the kind of chemical bonds inherent to metals

Possibly it's because plastic molecules are covelantly linked to one another and are nonpolar and nonpolarizable (I think), whereas the metals are easily polarizable and the atoms are not covalently bonded to one another.[/b]

Must be the difference between ionic and covalent bonds, covalent are harder to break, takes more energy.

Originally posted by sonhouse
Must be the difference between ionic and covalent bonds, covalent are harder to break, takes more energy.

Actually, they're called metallic bonds in metal, not ionic or covelant. But yes, that's the idea.

Originally posted by AThousandYoung
Actually, they're called metallic bonds in metal, not ionic or covelant. But yes, that's the idea.

Ah yes, thanks, had forgotten about that one. Loose shared electrons making conduction possible. BTW, did you hear about the latest finding on neutrons, they sussed out the fact that it is very complex internally, with three separate layers of charge, an inner charge, positive I think, then a middle layer of negative charge and a thin outer layer of positive again, making the whole thing electrically neutral. Mostlyl neutral anyway.

Originally posted by sonhouse
Ah yes, thanks, had forgotten about that one. Loose shared electrons making conduction possible. BTW, did you hear about the latest finding on neutrons, they sussed out the fact that it is very complex internally, with three separate layers of charge, an inner charge, positive I think, then a middle layer of negative charge and a thin outer layer of positive again, making the whole thing electrically neutral. Mostlyl neutral anyway.

The three quark model of a neuton, is that obsolete nowadays?
And each quark is a point particle? Or a some kind of vibrating string in a multidimensionl space? Or something?

How is it possible to make observations about the internal structure of a neutron anyway? With what method?

Originally posted by sonhouse
Ah yes, thanks, had forgotten about that one. Loose shared electrons making conduction possible. BTW, did you hear about the latest finding on neutrons, they sussed out the fact that it is very complex internally, with three separate layers of charge, an inner charge, positive I think, then a middle layer of negative charge and a thin outer layer of positive again, making the whole thing electrically neutral. Mostlyl neutral anyway.

Ooh, really? That sounds interesting.

Originally posted by FabianFnas
The three quark model of a neuton, is that obsolete nowadays?
And each quark is a point particle? Or a some kind of vibrating string in a multidimensionl space? Or something?

How is it possible to make observations about the internal structure of a neutron anyway? With what method?

I think they figured it out at Cern, will have to get back with you on confirmation and I think it's too early yet for the theory boys to munch on it. I'll try to find the original source. New Scientist maybe.