Sciencemadness Discussion Board

Two questions

IrC - 2-8-2005 at 20:04

Reading one of the PDF's from the lanl data Polverone put up, I find a report where uranium in water with low oxygen forms the pyrophoric hydride rather than the hydroxide. If I put my U238 into water with an aquarium pump with bubbler stone going, would this allow the hydroxide to form? How other than a fire and radioactive smoke I really don't want in my face could I tell which was formed? Just by PH in water solution alone i.e., the hydroxide would be a basic solution?

Also, what is a good way to make dysprosium metal turn into the oxide Dy2O3? Most of my lanthanides I can just cover to keep dust out and let it sit in air in a beaker and wait. For the Dy though, even with an oxy-mapp flame all I can do is actually melt it and the alumina crucible until they are one with the universe (and each other). No way does heat make Dy form oxide, at least at any temperature I can obtain, and certainly not at a temperature any container I have can withstand. I would prefer some electrolytic method if possible rather than messing around with trying to dissolve the metal in some acid or other more dangerous method like that.

Any ideas?

PS: I could handle it if the result was a hydroxide or carbonate, and a water soluble salt would be useful, but I really do not want to mess with dissolving it in acids and the salt cannot be any halogen, or sulfur salt (also out is phosphorus, carbide, cyanide, etc.). Having spent much time playing with the chemistry of glow powders and superconductors, I find interesting connections between the two, but certain elements such as those mentioned inhibit both effects.

[Edited on 3-8-2005 by IrC]

12AX7 - 3-8-2005 at 00:48

Dunno about the U, it's amphoteric, no? So it wouldn't really dissolve or produce much pH in either direction.

As for Dy, it doesn't corrode like the others? Weird. Could you anodize it in a salt solution?

Tim

IrC - 3-8-2005 at 10:36

Don't know on the Dy, have not learned that much about anodizing. It is always in chunks, would be hard to use as electrode and I would not want to drill or machine it as that may create slight impurities of other metals. Maybe I can find a long piece I can loop a wire around and keep the wire above the solution. Do not want halides in there, will have to give thought and study to this.

On the U238, the PDF says in distilled water it is attacked producing pyrophoric "powders". Hydrides are mentioned in low O2 air, I am just asuming one of the "powders" is the hydroxide. ? I do know they say in low O2 moist air it corrodes into hydrides and pyrophorics (?), in moist air with lots of O2 into non pyrophoric oxides and lower oxides. Not really sure beyond that, I have never really known how to figure a way to control which valence there will be when there is a bunch of them possible. Well, maybe extremes, but between one number and the next I still need to learn much about valence and orbitals (and what controls what?).

The PDF is 00371970 on DVD 1, "Corrosion of Uranium in moist air" by James T. Waber and G.T. Sturdy.

Oh yeah I forgot. With nearly all my Lanthanides they keep vanishing, it is a fight to keep them around even when well sealed, or covered in oil, and such. With Gd, and Dy the opposite is true. I can threaten them with a blowtorch, shotgun, you name it, nada. I guess I should file those elements for now. For the activator you need to use a 2 or 3 reduced to a 2 with H2 (and there are few choices for multiple reasons), and a 3 for the co-activator. Funny but superconductors seem to care about this as well as laser materials or glow powders, although I am not sure what this has to do with Cooper pairs. When I find Cooper I'll ask about it.

It is so hard to find cheap salts of these metals. One link posted around here somewhere has a good list, but I am not rich. They want over 50 dollars a pound for bismuth, where it averages 7 dollars a pound on Ebay, just to give a comparison about what a big rip off almost every commercial supplier I can find is. I am sure these are the guys with the $20,000 toilet seats.


[Edited on 4-8-2005 by IrC]