cnidocyte - 22-8-2010 at 05:01
I know the chemistry behind the electrolysis of an NaCl solution but what happens with less reactive metals like Ag or Mn when their anion is freed?
Do they electroplate the anode? MnO2 for example, if I smear some MnO2 on a graphite anode in water then apply some voltage what would happen? I'm
guessing the O2 would be formed at the cathode but would the anode be electroplated with Mn?
woelen - 22-8-2010 at 12:03
Think of it carefully.
MnO2 must be reduced in order to make Mn of it. What are the conditions at or near the anode? Are they reducing? Think of Cl(-) ions being
converted to Cl2-gas. Is this reduction or oxidation?
Having though over the above, what do you think will happen? Do you think Mn-metal can be formed at the anode?
And how do you think O2 can be formed at the cathode from MnO2?
Metals can plate the cathode (which is reducing). Silver can be plated on e.g. a clean and smooth copper surface. Even Mn-metal (which is quite
reactive and not noble at all) can be plated at a cathode.
cnidocyte - 22-8-2010 at 12:38
Oh yeah I was thinking of voltaic cells being the source of electrons. Other way around in electrolysis though. I'm guessing Cl- ions being converted
to Cl2 oxidation since the anion has its full octet. Same goes for O2.