Hi
Last class my teacher started talking about electrolysis, the first example was the classical electrolysis of a solution of NaCl in water. To explain how we'd find out the products she went trough a long process involving ions and OH- and metals that were more reactive and less reactive than hydrogen...or something like that. Well in the end she concluded we'd obtain NaOH in the solution and H2 and Cl2 at the electrodes.
I then asked her 'but teacher, wouldn't it be simpler if I imagined the electrolysis of molten NaCl obtaining pure Na and Cl2 and then though like this: Does Cl2 reacts with water? No, then I'd obtain Cl2. Does Na reacts with water? Well, then what we get? 2 Na + 2 H2O -> 2 H2 + 2 NaOH, therefore we'd obtain H2 and NaOH at the other electrode. She got a little puzzled with this methoed and we tried it with other reactions, with AgNO3 the product would be Ag +NO3 since none of them reacts with water. Then with a solution of ZnSO4 I concluded we'd obtain Zn at one electrode and either SO2 or SO3 and O2 at the other electrode...and realized the SO3 (if it was SO2 it could react with he O2 anyway) would form...H2SO4 in the solution, which would then react with the Zn forming...H2 and ZnSO4! And after that I realized the ZnSO4 would be just a catalyst! Well I know it may not look like much but I kinda concluded that without prior basis, I mean I had no idea that it would be a catalyst until I concluded the
electrolysis would only be yielding O2 and H2
If anyone could tell me if this was merely a lucky coincidence, or if its in fact another way of seeing the same thing (since for the 'common' method I'd need to have that table of things that react or not with the hydrogen and with 'my' method I'd need to know if the product reacts or no with water, it does look pretty much like 2 ways of seeing the same thing)
Well thanks for your Patience reading all this and... oh I almost forgot...the teacher said that in electrolysis of water we'd had H+ and OH- at the electrodes...and well its quite easy to see that they'd pair up to form H2 and H2O and O2...well, could anyone explain me why OH- forms water and oxygen instead of H2O2 (which would be pretty nice considering it's properties ;p)
Once more thanks for reading all this and any answers will be greatly appreciated!