[cvn]

Greetings  

I've got a chemistry question. I am asking this question here, because my chem teacher marked me wrong regarding an electrolysis qns. It is regarding the electrolysis of dilute hydrochloric acid. Just needa get some explanation here.

In the chemistry textbook, it states that OH^- will be produced, unless the ions contain Clorine ions or Bromine ions. But because it is dilute HCl, which means it has little Clorine ions, how can Clorine gas be formed at the anode?

Should the answer be displacement of OH^- instead of Chlorine ions?  

[AWK]

Diluted HCl  contains Cl- anions and H3O+ cations, and just these ions migrate to electrodes. OF course you can also take into account a very small amount of OH- anions (but they are diminished by an equilibrium Kw=[H3O+][OH-]).
Also, this may depend on the voltage used.
The major products of electrolysis should be H2 and Cl2

[xiankai]

chlorine ions have a greater negative elctrode potential than hydroxide ions by a quite high degree, to the extent that a small concentration of Cl- anions will be displaced preferentially to hydroxide ions.