Hboomans
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Aluminium amalgam
Can someone help me with a good preparation of an aluminium amalgam because i'm sure i'm doing something wrong.
I was making an aluminium amalgam by a 2% solution of Mercury(ii)Nitrate in 200ml distilled water
I've cut 50gr aluminium foil in squares 2x2cm and put them in a beaker. Then i've put the solution over the aluminium and let it sit for a couple
minutes till hydrogen gas is vissible.
After a few minutes I've discarded the mercury solution and washed the alu foil with water. But when the water came in contact with the alu foil the
reaction started and almost all alu foil disolved.
What have I done wrong??
[Edited on 30-4-2014 by Hboomans]
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leu
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Mercuric Nitrate is less soluble so it takes longer to get an amalgamation going than with mercuric chloride  The mercuric ion can serve as a catalyst turning aluminum foil into aluminum hydroxide which produces hydrogen gas
during the reaction  Mercuric Iodide is more soluble than mercuric nitrate and
thus might be more suited to your needs 
Chemistry is our Covalent Bond
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macckone
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Try using a more dilute solution of nitrate or a thicker grade of
aluminum foil with a larger quantity of foil.
It sounds like you are forming amalgam it is just too reactive.
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GoldGuy
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You are using 5-10 times the amount of mercury necessary
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CycloKnight
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I've always had better success with sliced up aluminium pie tins. When thin aluminium foil has been consumed the surface area becomes very high and
the reaction can be very uncontrollable (depending on application). Thicker Al is also a lot less work to slice up (per gram) with some heavy duty
scissors.
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Hboomans
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I've done the amalgamation this time with the information you all gave me.
I've cut 30gr aluminium foil in sqaures about 2.5cm x 2.5cm and put them in a coffee grinder for a few seconds (because i've read this on the internet
about the coffee grinder)
I've placed the aluminium foil in a beaker and put 500ml h2o over the foil. The h2o i've made this first in a plastic bottle with 400mg mercury
nitrate, after about 10mins I saw that amalgamation has started so after that i've let it amalgamate for approx. another 10min.
After the amalgamation I discarded the h2o.
Now i've put the aluminium in my reaction vessel but nownothing happend, waited for 15min. still nothing happens. So I considerd putting another 400mg
mercury in the reaction vessel, after 2min. the reaction became so violent that it blows out of the condensor.
The foil I used i've measured it and it was .02mm so I've fold it once to get .04mm
What could have gone wrong??
I'm thinking of using aluminium barbeque trays the are .12mm thick. The reaction would be less violent, but the reaction would take longer. But does
anyone now how much longer the reaction will take place? Is there a way I can calculate that?
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Nicodem
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Thread Moved
3-5-2014 at 09:10 |
zed
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Umm. I had a buddy that used to run reductions with Aluminum Amalgam. Utilized a bathtub full of ice, and small, portion-wise additions of
ingredients to control the vigor of reaction.
That blowing out the condensor event....it isn't good. Commonly vents lots of hydrogen into the room, where it may mix with air and detonate. Not
healthy for living things.
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leu
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The time taken for the reaction to run to completion depends on what substrate is being reduced The fact that the contents of the reaction vessel were ejected through the condenser says that the substrate that you
posted questions about in another thread recently results in a rather exothermic reaction which is what caused the new decorative markings on the
ceiling  Your equipment isn't adequate for what you're trying to do in it, so
maybe you should study the subject more thoroughly before making another attempt at redecorating  There's plenty of information about your queries available online already so there was really no need for this thread
to be posted
Chemistry is our Covalent Bond
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