Anions and cations are the charge carriers within the cell. At the left-hand electrode,
copper is oxidized to copper ions, giving up electrons to the electrode. As
shown in Figure 18-3, the copper ions formed move away from the copper electrode
into the bulk of solution, while anions, such as sulfate and hydrogen sulfate
ions, migrate toward the copper anode. Within the salt bridge, chloride ions migrate
toward and into the copper compartment, and potassium ions move in the
opposite direction. In the right-hand compartment, silver ions move toward the
silver electrode where they are reduced to silver metal, and the nitrate ions move
away from the electrode into the bulk of solution.