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Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: ADJohnsonUK on October 28, 2019, 04:57:01 AM

Title: Electrolysis of Potassium Carbonate?
Post by: ADJohnsonUK on October 28, 2019, 04:57:01 AM
Hi everyone,

I wanted to check what products might form in electrolysis of Potassium Carbonate solution, using copper electrodes. Am I correct in thinking that some copper carbonate, or some other green substance would form on the anode?

I searched quite a few places (including this forum) but couldn't find a similar question....

Andrew Johnson
Title: Re: Electrolysis of Potassium Carbonate?
Post by: AWK on October 28, 2019, 05:22:31 AM
You will obtain [Cu(CO3)2]2- blue solution that can also undergo electrolysis.
Title: Re: Electrolysis of Potassium Carbonate?
Post by: ADJohnsonUK on October 28, 2019, 05:50:34 AM
Thanks - is there any likelihood that a greenish deposit would form on the anode too?
Title: Re: Electrolysis of Potassium Carbonate?
Post by: AWK on October 28, 2019, 06:20:23 AM
From an electrochemical (scientific) point of view, it doesn't make sense. Basic copper carbonate is practically non-conductive and hinders further electrolysis. This compound can be easily obtained in the laboratory. Patination of copper and copper alloys is also well known. Auguste Rodin also knew the completely cost-free method.
https://www.wikiwand.com/en/Patina
Title: Re: Electrolysis of Potassium Carbonate?
Post by: ADJohnsonUK on October 28, 2019, 06:28:21 AM
Thanks - I was just interested in whether a green deposit would form on the anode. I wasn't really thinking of using this method to make copper carbonate or anything like that - I realise it's freely available. I was trying to understand some claims in a YouTube video (which are almost certainly bogus). i.e. from my (fairly limited) knowledge of electrolysis, I thought that copper carbonate was probably forming on the electrode - due to some secondary reaction - but wanted to ask someone more knowledgeable!
Title: Re: Electrolysis of Potassium Carbonate?
Post by: AWK on October 28, 2019, 06:51:29 AM
For this purpose, it is better to start with simpler electrolysis models!