How will the pH of brine (aq. NaCl solution) be affected when it is electrolyzed?

NaCl (aq)Na+ (aq) + Cl (aq)


Cathode: H2O(l ) + e 1/2 H2(g) + OH (aq)


Anode: Cl (aq) 1/2 Cl2(g) + e


Overall reaction: NaCl(aq)+H2O(l)NaOH(aq)+H2(g)+Cl2(g)


The solution contains Na+ and OH- which combine to form NaOH.


Since NaOH is a strong base. It will turn the brine solution basic, and the pH of the solution will increase.


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