Lead acid cell: Discharging: Cathode

Gap-fill exercise

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!
Car_battery_discharging.gif

Electrons move from the [lead/lead dioxide] anode to the [lead/lead dioxide] cathode. There the electrons are [accepted/released] by positively charged ions in the lead dioxide electrode. The lead ions here have a [4+/2+] charge. Each lead [4+/2+] ion accepts two and is reduced to a lead [4+/2+] ion. [Oxidation/Reduction] occurs at this electrode. It is therefore called the [cathode/anode]. Because electrons are removed from the electrode in this way, it is charged [negatively/positively]. These lead ions combine with ions from the sulfuric acid electrolyte to form . Hydrogen ions from the sulfuric acid electrolyte combine with ions from the lead dioxide electrode to form .