Anode reaction in electrolysis with copper electrodes Steps:

• Anode is the positive electrode where oxidation occurs during electrolysis.
• Pure copper electrodes mean the anode material (Cu) can oxidize to Cu²⁺.
• Possible oxidations include Cu to Cu²⁺ (E°_ox = +0.34 V) or H₂O to O₂ (E°_ox = +1.23 V).
• Cu oxidizes preferentially as it requires less energy than water.

Why B is correct:

• It shows oxidation of the copper anode: Cu → Cu²⁺ + 2e⁻, per standard electrode potential rules.

Why the others are wrong:

• A: Describes reduction of Cu²⁺ to Cu, which happens at the cathode.
• C: Shows reduction of Ag⁺ to Ag, a cathode process.
• D: Indicates oxidation of Ag to Ag⁺, but no Ag metal is present at the anode.

Final answer: B