Care must be taken in choosing an electrolyte, since an anion from the electrolyte is in competition with the hydroxide ions to give up an electron. An electrolyte anion with less standard electrode potential than hydroxide will be oxidized instead of the hydroxide, and no oxygen gas will be produced. A cation with a greater standard electrode potential than a hydrogen ion will be reduced in its stead, and no hydrogen gas will be produced.
From what I understand, that bit states that certain electrolytes will stop the production of hydrogen gas and only oxygen gas and whatever gas from the electrolyte will be produced.
So I have two questions:
- What are some electrolytes that will stop the production of hydrogen gas in water electrolysis?
- What kind of water will be left behind if distilled water and an aforementioned electrolyte runs through electrolysis until all of the oxygen has been exhausted from the solution?
Please correct me if I'm misunderstanding anything.