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Chemistry / Re: Why does my black powder mixture not burn?

« on: 30/12/2019 10:10:52 »

Try weighing your components, 70/30 w/w. The density of charcoal is not reliable, so a mix by volume is unlikely to be optimum.

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Chemistry / Re: Is there an easy way to make oxalic acid at home without nitric acid?

« on: 09/04/2019 07:33:06 »

Page 499 of this old chemistry book states that oxalic acid can be acquired by mixing sawdust with potassium hydroxide: https://babel.hathitrust.org/cgi/pt?id=uc2.ark:/13960/t3tt4gz1p;view=1up;seq=527

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Chemistry / Re: Is there a way to separate the HCl from a mixture of salt and vinegar?

« on: 24/02/2019 01:29:08 »

Sodium chloride and vinegar will not be a useful combination for distilling HCl.

The pK_a of acetic acid (the acid in vinegar) is more than 12 units above the pK_a of hydrochloric acid (4.8 vs about –9), so the concentration of HCl could never be more than one trillionth of the concentration of acetic acid (and vinegar is about 5% acetic acid). Also, acetic acid and water are both fairly volatile, so you would probably just end up distilling water and then acetic acid, leaving sodium chloride behind.

It is possible to convert sodium chloride into hydrochloric acid by adding acid and distilling, if one uses much stronger acid with a much higher boiling point (and little to no water). I believe that sulfuric acid and phosphoric acid both would do the trick.

However, I should note that pure, hot, gaseous HCl is *extremely dangerous.* If you don't have the right equipment to condense it, or aren't working with enough ventilation, or something goes wrong, you could easily *permanently* damage your eyes and/or lungs. HCl can be purchased (in multiple concentrations), and this is a much safer way to get it (cold dilute aqueous solutions of HCl can still blind you, but at least you are unlikely to kill yourself with them...)

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Chemistry / Re: If i dry-distil sodium acetate, will i get acetone?

« on: 23/02/2019 12:21:15 »

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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Chemistry / Re: If i dry-distil sodium acetate, will i get acetone?

« on: 23/02/2019 12:07:03 »

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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Chemistry / Re: If i dry-distil sodium acetate, will i get acetone?

« on: 23/02/2019 09:43:29 »

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?