Concept:Fuel cells require an electrolyte to facilitate the internal transport of ions between the anode and the cathode while acting as an electrical insulator to force electrons through the external circuit.
Solution:- The traditional alkaline fuel cell (AFC), famous for its use in the Apollo space missions, utilizes an aqueous solution of Potassium Hydroxide (\( KOH \)).
- The \( KOH \) solution allows for the rapid mobility of hydroxide (\( OH^- \)) ions from the cathode to the anode, which is necessary to sustain the redox reactions.
Why other options are incorrect:Sodium chloride and sodium nitrate are not used because they do not provide the necessary \( OH^- \) ions or \( H^+ \) ions required for the standard hydrogen-oxygen half-reactions.
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