kryss
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Metal Powders
I have come across, form a number of sources, methods of making finely divided metal powders by reducing alcoholic solutions of metal acetates with
the likes of Hydrazine. A bit exotic perhaps but i cant help wondering what other reducing agents would work. Any ideas, the strongest i have is
Stannous Chloride - and i think its got water of crystallisation in it.
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BromicAcid
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Stannous Chloride is not going to cut it for any unusual reduction. If you need hydrazine you need a powerful reducing agent. Not much help but you
could always use the azide anion, the strongest reducing agent in aqueous solutions E = -3.33 
[Edited on 6/9/2004 by BromicAcid]
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kryss
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I've since discovered heating metal oxalates (in an inert atmosphere) also works - a lot of people are making superconductors and metal/metal
oxide catalysts this way.
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chemoleo
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Oh yes, and pyrophoric metals (i.e. iron oxalate). More dangerously though, explosive salts (silver oxalate).
Anyway.. bromic.. interesting note on the azides. Can this be actually used for decent reductions? how about -COOH to -CH2OH?  (enzymes do that quite well by the way )
Are you aware of some interesting ones, for aqueous reductions (aside from the above, which won't work)?
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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Tacho
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Vitamin C. Look here..
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bajamar
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Maybe irrelevant, but I was wondering that sodium metal could be formed by relesing a finely grinded NaN3 in an inert atmosphere heated to
sufficiently high temperature for decomposition to take place. At 350C sodium will be in a liquid phase, forming something like a fog. Maybe a nice
effect once the fog is reliesed outside. If the droplets were then rushed through an effective cooling system, Na dust could have been collected and
packaged under nitrogen. Unfortunately, I understand that the procedure would have been very challenging and expensive.
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BromicAcid
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Yes, sodium will result from heating the azide under controlled conditions without access to air. Recently my thoughts have turned to the thermal
decomposition of sodium borohydride which gives sodium, boron, and some strange polymetric compounds from what I have read. An easier way to make
sodium powder involves heating to the melting point under mineral oil with intense stirring, I believe other things like liquid parrafin and such are
added to give the correct density mineral oil for the perfect 'dust' of sodium suspended, which reminds me of the methods of mixing ethyl
alcohol with water to make the perfect colloidal phosphorus mixture.
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