[EliasDabbas]

Hi, I recently did a lab, and I'm having some trouble figuring out the net ionic equations... Im supposed to figure out what the products are from the electrolysis of 0.1 KNO3 solution using a power supply and 2 thin copper strips to take the power to the solution.

Here are the half reactions I think happened:

Anode: Cu ==> Cu+2 + 2e-     &     2H2O ==> O2(g) + 4H+ + 4e-1
Cathode: 2H20 + 2e- ==> H2 + 2OH-

Im pretty sure of the cathode reactions, but I'm somewhat unsure of the anode reactions, do both half reactions occur? The copper strips dissolve and the water turns to O2 and H+?

Should I write both anode reactions as the anode reaction? Or should I write just one?

Help would be appreciated.

[tamim83]

Im pretty sure of the cathode reactions, but I'm somewhat unsure of the anode reactions, do both half reactions occur? The copper strips dissolve and the water turns to O2 and H+?

Should I write both anode reactions as the anode reaction? Or should I write just one?

Both reactions can occur, the question is which one does.  What did you observe as you ran the reaction?  That will give you some clues as to what happened.  You can also look at the standard reduction potentials for each half reaction.  At the anode, the half reaction with the most positive reduction potential should occur.  The same goes for the cathode as well. 

Hope this helps some. 

[EliasDabbas]

Thanks! Helped alot!