I hate to suggest this in an era of hyperhysteria about toxic substances, but a mercury cathode would likely do the trick here. You just have a shallow layer of Hg at the bottom of your cell and make sure the wire that passes through the electrolyte to the the Hg is insulated. If you are careful, you can stir the electrolyte without disturbing the surface of the Hg cathode.
M. =============================================== --- On Fri 01/28, Robin van Spaandonk < [EMAIL PROTECTED] > wrote: From: Robin van Spaandonk [mailto: [EMAIL PROTECTED] To: [email protected] Date: Sat, 29 Jan 2005 09:45:30 +1100 Subject: Re: A question for the electrochemists In reply to Michael Foster's message of Thu, 27 Jan 2005 23:36:39 -0500:<br>Hi Michael,<br>[snip]<br>> Hi Robin,<br>><br>>I assume you mean potassium carbonate in an aqueous solution. If that is the case, you won't get any potassium metal at all. You need a molten non-aqueous potassium compound in order to do this, such as potassium chloride.<br><br>Yes, I do mean in an aqueous solution, though I don't mean a permanent layer of potassium. I realise full well that any potassium formed will react almost immediately with the surrounding water. However H+, or perhaps even water molecules will also be reduced at the cathode. What I am looking for is that combination of parameters that results in a maximal "turn over" of potassium ions, as opposed to the other reactions competing for the free electrons supplied by the cathode.<br><br><br>Regards,<br><br><br>Robin van Spaandonk<br><br>All SPAM goes in the trash unread.<br><br> _______________________________________________ Join Excite! - http://www.excite.com The most personalized portal on the Web!
