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Question
Write cathode and anode reaction in a fuel cell.
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Solution
Cell reactions in a fuel cell:
Oxidation at the anode (-):
Oxidation of hydrogen gas to water occurs at the anode.
2H2(g) + 4OH-(aq) →4H2O(l) + 4e-
Reduction at the cathode (+):
Reduction of oxygen gas to OH ions occurs at the cathode.
O2(g) + 2H2O(l) + 4e- → 4OH-(aq)
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