symboom
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diacetyl peroxide formation
ive used a mix of 5% vinegar and 3% peroxide to a piece of zinc to see if i could form zinc peroxide or is this diacetyl peroxide forming and i have
a precipitate of some white powder
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Adas
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This must be zinc peroxide. Diacetyl peroxide does not form so easily and it would react with organics in vinegar.
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symboom
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though organic what do you mean
white vinegar is made chemically. what i used
brown vinegar made from bacteria is what you must mean
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kavu
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Zinc dissolves in acetic acid to give Zn²⁺ ions. A commonly known procedure for synthesis of zinc peroxide is to react a zinc salt with an
aqueous solution of hydrogen peroxide. You have not given any information on the quantities used, so I'd say that the ppt contains mostly ZnO2 and ZnO
alongside with a cocktail of other zinc compounds.
A procedure for zinc peroxide is described for example in the recent article N. Singh, S. Mittala, K. Sood, P. Gupta CONTROLLING THE FLOW OF NASCENT
OXYGEN USING HYDROGEN PEROXIDE RESULTS IN CONTROLLING THE SYNTHESIS OF ZnO/ZnO2, Chalcogenide Letters, Vol. 7, No. 4, April 2010, p. 275-281
Synthesis of diacetyl peroxide, an extremely dangerous thing to do, calls for more concentrated acetic acid or acetic acid derivatives.
[Edited on 29-1-2012 by kavu]
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Adas
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Quote: Originally posted by kavu  | | Synthesis of diacetyl peroxide, an extremely dangerous thing to do, calls for more concentrated acetic acid or acetic acid derivatives.
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Yes, it can be made of acetyl chloride and BaO2, for example. If information given about DAP by Wiki is not exaggerated, it is really extremely
dangerous stuff.
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symboom
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yeah i guess i could have used my glacial acidic acid (from distilling it from sodium acetate with sulfuric acid.) but i was afraid of actyl peroxide
forming so i just used sore bought stuff.
zinc peroxide white to yellow powder seems right what i have.
any experiments to prove zinc peroxide formation
burning the filter paper it is on with it.
any suggestions?
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kotze
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Zinc peroxide vigorously reacts with sulfur when heated and forms shock-sensitive mixtures with it. I doubt you have much ZnO2 in your precipate
because of low H2O2 concentration. ZnO2 is best made by boiling ZnO with >30% H2O2 until dry. A dark yellow to orange powder is thus obtained which
is somewhat delicate to store - the slightest presence of moisture will cause the container to blast open.
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kavu
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You can determine the approximate composition by thermal decomposition of zinc peroxide to form zinc oxide. Weight a known amount of the product and
heat it. Cool it in a dessicator, weigh and repeat untill you get a constant weight. From the weight difference you can calculate the approximate
amount of zinc peroxide in your sample.
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MrHomeScientist
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| Quote: Originally posted by symboom | though organic what do you mean
white vinegar is made chemically. what i used
brown vinegar made from bacteria is what you must mean |
Organic chemistry is anything dealing with carbon-based molecules, regardless of how they were made. Acetic acid is classified as an organic acid,
whether it came from a flask or from living things.
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Adas
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Boiling H2O2? Really?
| Quote: Originally posted by kotze | | ZnO2 is somewhat delicate to store - the slightest presence of moisture will cause the container to blast open. |
Isn't moisture everywhere? Can you post any refference?
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kotze
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Yes you need to boil it down. ZnO2 is relatively temperature-stable and fixes most of the O-O before it decomposes. I made some myself years ago, from
ZnO, H2O2 and a little NH3. After filling it into a tight glass bottle it shattered the bottle, scattering glass and ZnO2 everywhere. The bottle was
washed shortly before and I probably didn't get it fully dry. ZnO2 is somewhat of a suspicious substance, I remember it crackled and flashed with a
blue flame when thrown onto a red-hot heating plate.
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Adas
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That seems very dangerous. But there is no such info on Wikipedia..
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entropy51
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Well that clinches it, doesn't it?
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Vikascoder
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But if you will heat the hydrogen peroxide there is a risk of detonation if some impurities are present
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