Graphite leads in electrolysis

  • Context: High School 
  • Thread starter Thread starter ufarad
  • Start date Start date
  • Tags Tags
    Electrolysis Graphite
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
1 reply · 3K views
ufarad
Messages
15
Reaction score
0
What is it about graphite leads that make them so much better for electrolysis than, say, copper leads? I tried it both ways, connecting leads to a battery and then sticking them in some water and with the graphite leads there was much more bubbling going on. So what is it about the graphite? Thanks.
 
Physics news on Phys.org
CO2 (g) + 4 H+ (aq) + 4 e- --> C (s) + 2 H2O (l) has an E0 of +0.20 V,
making carbon somewhat easier to oxidize than copper (E0 = +0.34).

So carbon electrodes do deteriorate slowly. The benefit is that their oxidation product (carbon dioxide) is a gas,
so it doesn't interfere much. And that carbon is simply a lot cheaper than e.g. copper (and especially platinum).