Sciencemadness Discussion Board

Copper acetate- Any ideas on what to do with it?

TriiodideFrog - 19-12-2020 at 02:01

A few years back, I made a batch of copper acetate crystals for no reason except their colour. Now, they are just sitting in my lab taking up space. Does anyone have any suggestions or ideas on what to do with them? Thanks:)

karlos³ - 19-12-2020 at 02:16

Wasn't the early absinthe, like some of the stuff Vincent van Gogh purportedly drank, coloured with copper acetate?
Or was that cupric acetate? :P
Oh, turns out I didn't knew that cuprous acetate is not a thing, thought Cu(I) and Cu(II) acetates would exist but no there is only one.

Jokes aside ok, I think the acetate salt of copper is one of the most well suited ones for the preparation of especially fine copper nanoparticles by reduction with borohydride(which is partially composed of copper boride then).
Interesting reducing agent and quite strong, can reduce stuff that plain borohydride can't reduce on its own.
The preparation has to be done fast and vigorous though, with lots of foaming and strong stirring, to get the black particles in the desired size and thus activity.

unionised - 19-12-2020 at 06:46

Quote: Originally posted by karlos³  
Wasn't the early absinthe, like some of the stuff Vincent van Gogh purportedly drank, coloured with copper acetate?

Have you ever tasted anything with a significant concentration of copper in it?

MidLifeChemist - 19-12-2020 at 09:46

I have mine sitting on a watch glass. It seems to hold up well in air and I admire it quite frequently.

>> for no reason except their colour.
I mean, that's exactly why you make it!

Bedlasky - 19-12-2020 at 09:59

https://woelen.homescience.net/science/chem/exps/index_trans...

karlos³ - 19-12-2020 at 14:29

Quote: Originally posted by unionised  
Quote: Originally posted by karlos³  
Wasn't the early absinthe, like some of the stuff Vincent van Gogh purportedly drank, coloured with copper acetate?

Have you ever tasted anything with a significant concentration of copper in it?

No and I don't plan, have you?
It seems to me that not much is needed though, and absinthe is bitter anyways, it might not take much to achieve that coloration.
And it was only contained in the cheaply produced ones, sometimes.

Amos - 20-12-2020 at 10:15

Both copper salts and antimony salts were sometimes added to improve the color and clouding properties when trying to stretch or even totally counterfeit absinthe. Sounds like drinking really cheap liquor was a bad idea even back then.

DraconicAcid - 20-12-2020 at 11:23

I've also read that copper salts were added to pickles to make them greener, and testing pickles with ammonia was used as a lecture demonstration.

unionised - 20-12-2020 at 11:52

Quote: Originally posted by karlos³  
Quote: Originally posted by unionised  
Quote: Originally posted by karlos³  
Wasn't the early absinthe, like some of the stuff Vincent van Gogh purportedly drank, coloured with copper acetate?

Have you ever tasted anything with a significant concentration of copper in it?

No and I don't plan, have you?
It seems to me that not much is needed though, and absinthe is bitter anyways, it might not take much to achieve that coloration.
And it was only contained in the cheaply produced ones, sometimes.


The world health organisation sets a limit for copper in drinking water, partly on the basis of taste rather than direct health consequences.
At levels above a few ppm the taste puts people off drinking and that, in turn, causes problems.

So, at what concentration do you think copper would make Absinthe green?
(Note; this may be a trick question).


TriiodideFrog - 23-12-2020 at 01:31

I added 6% hydrogen peroxide to copper acetate and the solution turned green.