Naked Science Forum
Non Life Sciences => Chemistry => Topic started by: Timothy Terwilliker on 23/02/2019 01:55:58
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i take sodium acetate from a baking soda and vinegar reaction and dry distill it will it make some acetone?
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No, that won't work.
You're right that reacting baking soda (sodium biocarbonate - NaHCO3) with acetic (ethanoic) acid - (CH3CHOOH) will produce sodium acetate NaCH3COO, which is the stuff used to flavour salt and vinegar crisps.
But acetate is in oxidised form and you would need to reduce it to produce the ketone (acetone).
I did see one claim that if you hear acetate salts to a reasonably high temperature (over 400C) and condense the vapour you'll get acetone. I cannot corroborate this though, and I've not fact-checked the claim.
Calling all chemists! Is this right, and what's the mechanism?
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Chris has correctly identified that the oxidation state of a carboxylic acid (like acetic acid) is higher than that of a ketone (like acetone), but there is another problem with this approach--molecules of acetic acid have two carbons in them, and molecules of acetone have three carbons in them.
There are ways of converting acetate to acetone, but they are much more complicated and less efficient than envisioned by the OP.
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which is the stuff used to flavour salt and vinegar crisps.
No it isn't.
That's this stuff
https://en.wikipedia.org/wiki/Sodium_diacetate
Heating sodium acetate (in the presence of sodium hydroxide) will produce methane.
It's true that one of the carbon atoms in acetate is rather oxidised, but the other one isn't.
You can get a reaction where some of the oxygens "swap partners" to give a more oxidised product (carbonate) and a less oxidised one (methane).
There's more about it here
https://www.researchgate.net/post/Do_you_know_of_any_procedure_for_preparing_methane_gas_from_sodium_acetate
However, if you want acetone, you can get it by heating calcium acetate.
And there's a bit more about that here.
http://www.prepchem.com/synthesis-of-acetone/
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which is the stuff used to flavour salt and vinegar crisps.
No it isn't.
That's this stuff
https://en.wikipedia.org/wiki/Sodium_diacetate
Thanks for pointing that out!