The number of faradays required to produce one mole of water from a hydrogen-oxygen fuel cell containing an aqueous alkali as an electrolyte is:
Correct answer: B. 2
- A. 1
- B. 2
- C. 3
- D. 4
Explanation
The overall reaction is 2H₂ + O₂ → 2H₂O. The half-reaction for hydrogen oxidation is H₂ → 2H⁺ + 2e⁻. To produce one mole of H₂O, one mole of H₂ must react, which involves the transfer of 2 moles of electrons. One mole of electrons is equivalent to one Faraday, so 2 Faradays are required.
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