fusso
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Attempt to make molten lead from oxalate
Intro:
This method is similar to the 'pyrophoric iron/nickel experiment' but with lead instead. The objective is also different as my goal isn't to make lead
powder either, but molten lead instead.
Wanted reaction:
PbC2O4(s) (+heat)-> Pb(l)+2CO2(g)
Procedure:
Add some PbC2O4(s) into a beaker. Heat strongly with blowtorch, first evenly around the beaker, then aim onto powder.
Results: Some white powder turned orange and some (dark) grey/gray.
Discussions & conclusions:
This experiment failed as no shiny metallic beads were formed. Possible reason is the lead being oxidised by atmos O2. Next time i'll try doing it in
a testtube instead.
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RustyShackleford
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Some metals decompose into oxide by
MC2O4 -> MO + CO + CO2
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fusso
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Yes but i didn't expect lead to be 1 of them as Pb is less reactive than Fe & Ni so i expect PbC2O4 to decomp into the metal more easily.
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Boffis
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No in this case the preparation of pyrophoric lead by this reaction is well known. To stop the lead so produced from rapid spontaneous oxidation you
would need an inert atmosphere and/or a low melting point flux. Caustic soda might work as a flux and you may be able to generate an inert atmosphere
in situ with something like pine resin (soldering flux), flour or cream of tartar (traditional alchemist's flux  ).
The problem is the very low decomposition temperature of lead oxalate, which is well below the melting point of lead and probably even caustic soda,
so lead may be formed before the flux can exclude atmospheric oxygen.
Is there any particular reason why you wish to use lead oxalate? Could you use lead carbonate plus flux and reducing agent?
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fusso
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1. the rxn between lead oxide/carbonate & reductant is done to death
2. the exp can be single-component, so it look neat for a demo exp, like the Fe & Ni versions
3. to compare with the Fe & Ni versions
4. the metal and reducer is in the same molecule, so rxn should be more complete (in theory) compared to mixing metal oxide+reducer due to more
'thorou mixing'
[Edited on 210222 by fusso]
[Edited on 210222 by fusso]
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Fulmen
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Boffis: NaOH won't work, that will only produce sodium plumbate. A CO2 atmosphere should work.
We're not banging rocks together here. We know how to put a man back together.
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Boffis
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Only at low temperatures at elevated temperatures (Mp of lead and above for certain) sodium plumbite is easily reduced. In fire assaying they use
cream of tartar and floor or starch for this purpose.
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Fulmen
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Fair enough, I was thinking aqueous conditions.
As for a practical demonstration a test tube would be a far better choice. Molten lead is pretty reactive, any air will oxidize it as soon as it's
formed. But as the reaction is "self blanketing" you should just heat a test tube from the outside with a loose fitting foil cap.
I kinda like the idea, creating liquid metal by heating a white powder. Hope you get it working.
We're not banging rocks together here. We know how to put a man back together.
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Fluorite
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Lead formate? Copper and silver formates decomposes to the pure metal right? Can this work with lead?
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Bedlasky
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Quote: Originally posted by Boffis  | | Is there any particular reason why you wish to use lead oxalate? Could you use lead carbonate plus flux and reducing agent? |
You don't need flux for making lead metal. I did preparation of lead in my first high school year at school lab. I just used lead oxide and active
charcoal for preparation - melted lead was then poured in to the water. Burning charcoal already formed an inert atmosphere during experiment.
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unionised
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How much of the lead do you plan to inhale?
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fusso
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Is this a /s or a serious question?
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vano
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I agree with others. The products are not the same for all metals. For example, the decomposition of indium trivalent oxalate produces a monovalent
oxide. Now I am preparing nitrate and I am going to try this.
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