HI~~

My electrolysis reactions are below:

Cathode: 2OH- --> 0.5 O2 + H2O

Anode: 2H2O ---> H2 + 2OH-

Initially, there are H2O + OH- in my solution. The problem is that how can I define the PH of the OH- in the solution? Or it can be translated by another form like mass or another. Can somebody help me~ Thank you.

pH is a derived quantity based on CONCENTRATION!

Thank you for your reply~

I know PH means concentration. But how can I define the concentration for my specifed species?

Can you get me some examples?

Thank you.

I hope I understand you properly. I just told you to convert pH into concentration by using its definition. pH=log_10(1/[H]) where [H] is concentration of H ions.

As far as concentration definition in Fluent is considered, you define it in terms of mass fraction.