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In the Daniell cell, which due to its simplicity is often used in classroom demonstrations, a wire and light bulb may connect the two electrodes.
Electrons that are “ pulled ” from the zinc anode travel through the wire, providing an electrical current that illuminates the bulb.
In such a cell, the sulfate ions play an important role.
Having a negative charge, these anions build up around the anode to maintain a neutral charge.
Conversely, at the cathode the copper ( II ) cations accumulate to maintain this neutral charge.
These two processes cause copper solid to accumulate at the cathode and the zinc electrode to " dissolve " into the solution.

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