Because a copper ion looses electrons, meaning it's negatively charged, and positives and negatives attract.
Because copper ions have a positive charge and are therefore attracted to the negative electrode
Copper ions are attracted to the negative electrode because they are positively charged and are drawn to the negatively charged cathode. At this cathode, they gain electrons and are reduced to form solid copper, which deposits on the electrode, increasing its mass. This process is fundamental in electrochemical reactions and applications like electroplating.
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