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In an electrolysis situation I have identified a slight brightness change on a copper electrode. What might have happened?

I'm dealing with different experiments and this reaction occurs in some of them. In this experiment I am doing an electrolysis using a water solution with $\ce{NaCl}$, a Lechanché and two copper bars. The brightness change happens on the anode.

I also get bubbles and a color change in the solution of the cathode, I'm guessing it is due to the reduction of water.

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If an aqueous solution of $\ce{NaCl}$ is electrolyzed between copper electrodes, the most important reaction taking place on the anode is the dissolution of copper, according to : $$\ce{Cu -> Cu^{2+} + 2e^-}$$ If the copper plate was well polished and shiny like a mirror, the corrosion reaction will first occur on the smallest crystals, which are inserted between bigger regular crystals. As a consequence, the surface will be irregularly attacked, and its aspect will loose its shiny appearance.

Of course, at the cathode, some Hydrogen gas is produced.

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My take on the possible chemistry starting with the electrolysis of salt water, which can produce some chlorine. The latter can further react with water as follows:

$\ce{Cl2 + H2O <=> H+ + Cl- + HOCl}$

The created Hypochlorous acid may react with cuprous (here present as a $\ce{Cu2O}$ on the copper metal electrode). A fenton-type reaction based on $\ce{HOCl}$ could then proceed as follows for $\mathrm{pH > 5}$:

$\ce{Cu(I) (s) + HOCl (aq) -> Cu(II) (aq) + ^.OH (aq) + Cl- (aq) }$

The dissolving of the $\ce{Cu2O}$ results in a de facto cleaning of the copper metal surface, which per a reference to quote:

Copper is a beautiful burnished-gold color when it is clean and well maintained, but like all metals, copper can become discolored when exposed to air and water.

For background on the fenton-type reaction, see "Fenton chemistry in biology and medicine" by Josef Prousek, to quote reaction (15) on page 2330, to quote:

For $\ce{Fe(II)}$ and $\ce{Cu(I)}$, this situation can be generally depicted as follows [20,39]

$\ce{ Fe(II)/Cu(I) + HOX -> Fe(III)/Cu(II) + HO^. + X- }$ (15)

where $\ce{X = Cl, ONO}$, and $\ce{SCN}$.

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