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Ah, of course.So, I change the MFD reason to well know to exist. |
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At least it wasn't a "just add water" |
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To be fair, if ice was both compressed into a more compact crystalline form and cooled to near absolute zero, it would take up less space than water. However, on looking at Wikipedia even VHDAI (Very High Density Amorphous Ice) only has a density of a quarter more than water, so it wouldn't help much. |
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But i want to fix this. Is there maybe a polymer which liberates water in some circumstances, or are there clathrates which contain water molecules? What about water of crystallisation? |
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I don't think it would take up less space, but i'm not at all convinced there couldn't be a dry powder from which water could be obtained, or that that powder would be useless. |
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It isn't "magic" and therefore we dispute any [M-F-D]s. It is possible to encapsulate water in tiny, tough "pellets" that can be moved as a powder, but then be disintegrated by the application of heat or a suitable solvent. Also, this is probably not "widely known to exist" otherwise at least one of the previous annotators would have mentioned it ... |
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//Someone should invent a method// |
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//microencapsulation// isn't saving space or weight |
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//spacecrafts// if your water is going to leak then so is the powder. I don't see any advantages (or many, anyways) for space travel: you can always freeze water, for instance, into a nicy shiny shell for your spaceship (or a couple foot thick layer of ice, with a thin aluminium cover to keep from boiling off) |
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In two places, the poster posits the powder would be of less mass than the water it produces. I'll second the [MFD] - magic. |
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Maybe some sort of metallic hydrogen? To reconstitute
water, just burn in an oxygen atmosphere (effectively, less
mass dry than wet, since it "steals" mass from the
atmosphere). No -- even lithium-doped, it would have to be
stored under pressure. Metastable metallic hydrogen? yes, if
it exists, or even can exist. How about hydrogen-
impregnated palladium nanoparticles? |
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// all you need is a bag of powder and some source of heat // |
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Only a person living near South or North pole could make much use of this idea. Yet, the idea is essentially reinventing "snow". So, the user must be writing from a place on Earth where never snows, yet the temperatures are always below the freezing point. I wonder, where that is. |
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Here at the halfbakery we do require a modicum of originality. This joke is older than dirt. |
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//all you need is a bag of powder and some source of heat//
OK, here goes...
The powder is not actually water, but rather a dessicant.
Open the pouch of dessicant and allow it to draw moisture out of the air.
Distill the moisture from the dessicant. This could be accomplished as follows:
-Construct a two-chambered vessel such that the two chambers are in contact with opposite sides of a Peltier heat pump. The vessels shall be connected via a small tube, but the assembly should be otherwise sealable.
- Place the saturated dessicant in the hot-side chamber and seal it.
- Turn on the peltier device.
- Wait for the water to evaporate from the dessicant and condense in the cold-side chamber.
- Open the cold side vessel and recover your water. |
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Very humid spaceship required for that one. I prefer the microencapsulation but i think water might behave rather strangely in that situation. It wouldn't be less massive, but it might have a use. |
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Further to what mouseposture said, there are several hydrides that react with oxygen to form water. Hydrides are currently being researched as a way of storing hydrogen which could be useful in the 'hydrogen economy'. Thus hydrides can serve the dual purposes of storing both energy and water. |
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//How about hydrogen- impregnated palladium nanoparticles?// Looks good... except: |
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Hydrogen fits into the structure of palladium at a maximum *theoretical* ratio of 1 H : 1 Pd. (The 900:1 ratio you see kicking around is volume:volume, and there's a huge density difference. 900:1 (v:v) is actually about 0.7 H : 1 Pd on a per-atom basis.) |
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Water stores hydrogen in a ratio of 2 H : 1 O; therefore, considering the atomic weight of oxygen is 16 and palladium is 106, you could theoretically store enough hydrogen in 107 grams of saturated palladium to create 9 grams of water. Practically, call it about 6.3 grams. |
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//No heavy bottles to carry around.// If it's "bottles" that's objectionable, we can help. If "heavy" is undesireable, tough. Drink less. |
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