Concept:A hydrogen-oxygen fuel cell continuously converts the chemical energy of a fuel (\( H_2 \)) and an oxidant (\( O_2 \)) directly into electrical energy.
Solution:- In a standard Apollo-era fuel cell, Hydrogen is oxidized at the anode and Oxygen is reduced at the cathode.
- The overall highly exothermic cell reaction is: \( 2H_2 + O_2 \rightarrow 2H_2O \).
- One of the most significant advantages of this specific power source in aerospace engineering is that its only chemical byproduct is pure, perfectly potable liquid water, which astronauts utilize for drinking.
Why other options are incorrect:Nickel-cadmium, lead-acid accumulators, and alkaline batteries are closed-system storage cells that do not produce harvestable drinking water as a byproduct.
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